<PAGE>
 
                                                                    EXHIBIT 10.2


--------------------------------------------------------------------------------

                            PARTICIPATION AGREEMENT
 
                         Dated as of December 30, 1997
 
                                     among
 
 
                       AOR SYNTHETIC REAL ESTATE, INC.,
    as the Construction Agent, as the Lessee and as a Tranche A Guarantor,
 
 
                      AMERICAN ONCOLOGY RESOURCES, INC.,
                as the Guarantor and as a Tranche A Guarantor,
 
 
                 THE VARIOUS PARTIES HERETO FROM TIME TO TIME,
                      as the other Tranche A Guarantors,
 
                  FIRST SECURITY BANK, NATIONAL ASSOCIATION,
                     not individually, except as expressly
                stated herein, but solely as the Owner Trustee
                          under the AOR Trust 1997-1,
 
 
          THE VARIOUS BANKS AND OTHER LENDING INSTITUTIONS WHICH ARE 
               PARTIES HERETO FROM TIME TO TIME, as the Holders,
 
 
          THE VARIOUS BANKS AND OTHER LENDING INSTITUTIONS WHICH ARE 
               PARTIES HERETO FROM TIME TO TIME, as the Lenders,
 
                                      and
 
 
                          FIRST UNION NATIONAL BANK,
                         as the Agent for the Lenders
                    and respecting the Security Documents,
                 as the Agent for the Lenders and the Holders,
                       to the extent of their interests
 
--------------------------------------------------------------------------------
<PAGE>
 
                               TABLE OF CONTENTS

<TABLE> 
<CAPTION> 
<S>                                                                               <C> 
                                                                                  Page

SECTION 1.  THE LOANS................................................................2

SECTION 2.  HOLDER ADVANCES..........................................................3

SECTION 3.  SUMMARY OF TRANSACTIONS..................................................3
     3.1. Operative Agreements.......................................................3
     3.2. Property Purchase..........................................................3
     3.3. Construction of Improvements; Commencement of Basic Rent...................4

SECTION 4.  THE CLOSINGS.............................................................4
     4.1. Initial Closing Date.......................................................4
     4.2. Initial Closing Date; Property Closing Dates; Acquisition Advances;
          Construction Advances......................................................4

SECTION 5.  FUNDING OF ADVANCES; CONDITIONS PRECEDENT; REPORTING REQUIREMENTS ON
            COMPLETION DATE;  THE LESSEE'S DELIVERY OF NOTICES; RESTRICTIONS ON
            LIENS....................................................................4
     5.1. General....................................................................4
     5.2. Procedures for Funding.....................................................5
     5.3. Conditions Precedent for  the Lessor, the Agent, the Lenders and the
          Holders Relating to the Initial Closing Date and the Advance of Funds
          for the Acquisition of a Property..........................................7
     5.4. Conditions Precedent for the Lessor, the Agent, the Lenders and the
          Holders Relating to the Advance of Funds after the Acquisition Advance....12
     5.5. Additional Reporting and Delivery Requirements on Completion Date and
          on Construction Period Termination Date...................................13
     5.6. The Construction Agent Delivery of Construction Budget Modifications......14
     5.7. Restrictions on Liens.....................................................14
     5.8. Accession Agreement Requirements - New Tranche A Guarantors...............14
     5.9. Maintenance of AOR Synthetic Real Estate, Inc. as a Wholly-Owned
          Entity....................................................................15
     5.10. Post-Closing Requirements Regarding Certain Properties for Which
           Advances are Made on the Initial Closing Date............................15

SECTION 6.  REPRESENTATIONS AND WARRANTIES..........................................15
     6.1. Representations and Warranties of the Borrower............................15
     6.2. Representations and Warranties of Each Credit Party.......................18

SECTION 7. PAYMENT OF CERTAIN EXPENSES..............................................23
     7.1. Transaction Expenses......................................................23
     7.2. Brokers' Fees.............................................................24
     7.3. Certain Fees and Expenses.................................................25

</TABLE> 
<PAGE>
 
<TABLE> 
<CAPTION> 
<S>                                                                               <C> 

     7.4. Facility Fee..............................................................25
     7.5. Administrative Fee........................................................26

SECTION 8.  OTHER COVENANTS AND AGREEMENTS..........................................26
     8.1. Cooperation with the Construction Agent or the Lessee.....................26
     8.2. Covenants of the Owner Trustee and the Holders............................26
     8.3. Credit Party Covenants, Consent and Acknowledgment........................28
     8.4. Sharing of Certain Payments...............................................31
     8.5. Grant of Easements, etc...................................................32
     8.6. Appointment of the Agent by the Lenders, the Holders and the Owner
          Trustee...................................................................32
     8.6B. Appointment of the Lessor by the Lenders and the Holders.................33
     8.7. Collection and Allocation of Payments and Other Amounts...................33
     8.8. Release of Properties, etc................................................36

SECTION 9.  CREDIT AGREEMENT AND TRUST AGREEMENT....................................37
     9.1. The Construction Agent's and the Lessee's Credit Agreement Rights.........37
     9.2. The Construction Agent's and the Lessee's Trust Agreement Rights..........37

SECTION 10.  TRANSFER OF INTEREST...................................................38
     10.1. Restrictions on Transfer.................................................38
     10.2. Effect of Transfer.......................................................39

SECTION 11.  INDEMNIFICATION........................................................39
     11.1. General Indemnity........................................................39
     11.2. General Tax Indemnity....................................................42
     11.3. Increased Costs, Illegality, etc.........................................46
     11.4. Funding/Contribution Indemnity...........................................48
     11.5  EXPRESS INDEMNIFICATION FOR ORDINARY NEGLIGENCE, STRICT LIABILITY,
           ETC......................................................................49

SECTION 12.  MISCELLANEOUS..........................................................50
     12.1. Survival of Agreements...................................................50
     12.2. Notices..................................................................50
     12.3. Counterparts.............................................................53
     12.4. Terminations, Amendments, Waivers, Etc.; Unanimous Vote Matters..........53
     12.5. Headings, etc............................................................54
     12.6. Parties in Interest......................................................55
     12.7. GOVERNING LAW; SUBMISSION TO JURISDICTION; WAIVER OF JURY TRIAL;
           VENUE; ARBITRATION.......................................................55
     12.8. Severability.............................................................57
     12.9. Liability Limited........................................................57
     12.10. Rights of the Lessee....................................................58
     12.11. Further Assurances......................................................58
     12.12. Calculations under Operative Agreements.................................59
     12.13. Confidentiality.........................................................59
</TABLE> 

                                      iii
<PAGE>
 
<TABLE> 
<CAPTION> 
<S>                                                                               <C> 
     12.14. Financial Reporting/Tax Characterization................................59
     12.16 USURY SAVINGS PROVISION..................................................60
     12.17 Chapter 346 of the Texas Finance Code....................................61
</TABLE> 

EXHIBITS

A - Form of Requisition - Sections 4.2, 5.2, 5.3 and 5.4

B - Form of Outside Counsel Opinion for the Lessee - Section 5.3(j)

C -[Intentionally Omitted]

D - Form of Officer's Certificate - Section 5.3(z)

E- Form of Officer's Certificate - Section 5.3(aa)

F - Form of Officer's Certificate - Section 5.3(bb)

G - Form of Officer's Certificate - Section 5.3(cc)

H - Form of Outside Counsel Opinion for the Owner Trustee - Section 5.3(dd)

I - Form of Outside Counsel Opinion for the Lessee - Section 5.3(ee)

J - Form of Officer's Certificate - Section 5.5

K - Form of Accession Agreement - Section 5.8

L - Description of Material Litigation - Section 6.2(d)

M - States of Incorporation/Formation and Principal Place of Business of each
    Tranche A Guarantor - Section 6.3(i)

N - Form of Compliance Certificate and Covenant Compliance Worksheet - Section
    8.3(l)

Appendix A - Rules of Usage and Definitions


                                      iv
<PAGE>
 
                            PARTICIPATION AGREEMENT

     THIS PARTICIPATION AGREEMENT dated as of December 30, 1997 (as amended,
modified, extended, supplemented, restated and/or replaced from time to time,
this "Agreement") is by and among AOR SYNTHETIC REAL ESTATE, INC., a Delaware
corporation (the "Lessee" or the "Construction Agent" or a "Tranche A
Guarantor"); AMERICAN ONCOLOGY RESOURCES, INC., a Delaware corporation, (the
"Guarantor" or a "Tranche A Guarantor"), the various entities which are parties
hereto from time to time as guarantors of the Tranche A Loans (subject to the
definition of Tranche A Guarantors in Appendix A hereto, individually a "Tranche
A Guarantor" and collectively, the "Tranche A Guarantors"), FIRST SECURITY BANK,
NATIONAL ASSOCIATION, a national banking association, not individually (in its
individual capacity, the "Trust Company"), except as expressly stated herein,
but solely as the Owner Trustee under the AOR Trust 1997-1 (the "Owner Trustee",
the "Borrower" or the "Lessor"); the various banks and other lending
institutions which are parties hereto from time to time as lenders (subject to
the definition of Lenders in Appendix A hereto, individually, a "Lender" and
collectively, the "Lenders"); FIRST UNION NATIONAL BANK, a national banking
association, as the agent for the Lenders and respecting the Security Documents,
as the agent for the Lenders and the Holders, to the extent of their interests
(in such capacity, the "Agent"); the various banks and other lending
institutions which are parties hereto from time to time as holders of
certificates issued with respect to the AOR Trust 1997-1 (subject to the
definition of Holders in Appendix A hereto, individually, a "Holder" and
collectively, the "Holders"). Capitalized terms used but not otherwise defined
in this Agreement shall have the meanings set forth in Appendix A hereto.

     In consideration of the mutual agreements herein contained and other good
and valuable consideration, the receipt of which is hereby acknowledged, the
parties hereto hereby agree as follows:


                            SECTION 1.  THE LOANS.

     Subject to the terms and conditions of this Agreement and in reliance on
the representations and warranties of each of the parties hereto contained
herein or made pursuant hereto, the Lenders have agreed to make Loans to the
Lessor from time to time in an aggregate principal amount of up to the aggregate
amount of the Commitments of the Lenders in order for the Lessor to acquire the
Properties and certain Improvements, to develop and construct certain
Improvements in accordance with the Agency Agreement and the terms and
provisions hereof and for the other purposes described herein, and in
consideration of the receipt of proceeds of the Loans, the Lessor will issue the
Notes. The Loans shall be made and the Notes shall be issued pursuant to the
Credit Agreement. Pursuant to Section 5 of this Agreement and Section 2 of the
Credit Agreement, the Loans will be made to the Lessor from time to time at the
request of the Construction Agent in consideration for the Construction Agent
agreeing for the benefit of the Lessor, pursuant to the Agency Agreement, to
acquire the Properties, to acquire the Equipment, to construct certain
Improvements and to cause the Lessee to lease the Properties, each in 

                                       2

<PAGE>
 
accordance with the Agency Agreement and the other Operative Agreements. The
Loans and the obligations of the Lessor under the Credit Agreement shall be
secured by the Collateral.


                         SECTION 2.  HOLDER ADVANCES.

     Subject to the terms and conditions of this Agreement and in reliance on
the representations and warranties of each of the parties hereto contained
herein or made pursuant hereto, on each date Advances are requested to be made
in accordance with Section 5 hereof, each Holder shall make a Holder Advance on
a pro rata basis to the Lessor with respect to the AOR Trust 1997-1 based on its
Holder Commitment in an amount in immediately available funds such that the
aggregate of all Holder Advances on such date shall be three percent (3%) of the
amount of the Requested Funds on such date; provided, that no Holder shall be
obligated for any Holder Advance in excess of its pro rata share of the
Available Holder Commitment. The aggregate amount of Holder Advances shall be up
to the aggregate amount of the Holder Commitments. No prepayment or any other
payment with respect to any Advance shall be permitted such that the Holder
Advance with respect to such Advance is less than three percent (3%) of the
outstanding amount of such Advance, except in connection with termination or
expiration of the Term or in connection with the exercise of remedies relating
to the occurrence of a Lease Event of Default. The representations, warranties,
covenants and agreements of the Holders herein and in the other Operative
Agreements are several, and not joint or joint and several.


                     SECTION 3.  SUMMARY OF TRANSACTIONS.

     3.1. OPERATIVE AGREEMENTS.

     On the date hereof, each of the respective parties hereto and thereto shall
execute and deliver this Agreement, the Lease, each applicable Ground Lease, the
Agency Agreement, the Credit Agreement, the Notes, the Trust Agreement, the
Certificates, the Security Agreement, each applicable Mortgage Instrument and
such other documents, instruments, certificates and opinions of counsel as
agreed to by the parties hereto.

     3.2. PROPERTY PURCHASE.

     On each Property Closing Date and subject to the terms and conditions of
this Agreement (a) the Holders will each make a Holder Advance in accordance
with Sections 2 and 5 of this Agreement and the terms and provisions of the
Trust Agreement, (b) the Lenders will each make Loans in accordance with
Sections 1 and 5 of this Agreement and the terms and provisions of the Credit
Agreement, (c) the Lessor will purchase and acquire good and marketable title to
or ground lease pursuant to a Ground Lease, the applicable Property, each to be
within an Approved State, identified by the Construction Agent, in each case
pursuant to a Deed, Bill of Sale or Ground Lease, as the case may be, and grant
the Agent a lien on such Property by execution of the required Security
Documents, (d) the Agent, the Lessee and the Lessor shall execute and 

                                       3
<PAGE>
 
deliver a Lease Supplement relating to such Property and (e) the Term shall
commence with respect to such Property.

     3.3. CONSTRUCTION OF IMPROVEMENTS; COMMENCEMENT OF BASIC RENT.

     Construction Advances will be made with respect to particular Improvements
to be constructed and with respect to ongoing Work regarding the Equipment and
construction of particular Improvements, in each case, pursuant to the terms and
conditions of this Agreement and the Agency Agreement. The Construction Agent
will act as a construction agent on behalf of the Lessor respecting the Work
regarding the Equipment, the construction of such Improvements and the
expenditures of the Construction Advances related to the foregoing. The
Construction Agent shall promptly notify the Lessor upon Completion of the
Improvements and the Lessee shall commence to pay Basic Rent as of the Rent
Commencement Date.


                           SECTION 4.  THE CLOSINGS.

     4.1. INITIAL CLOSING DATE.

     All documents and instruments required to be delivered on the Initial
Closing Date shall be delivered at the offices of Moore & Van Allen, PLLC,
Charlotte, North Carolina, or at such other location as may be determined by the
Lessor, the Agent and the Lessee.

     4.2. INITIAL CLOSING DATE; PROPERTY CLOSING DATES; ACQUISITION ADVANCES;
     CONSTRUCTION ADVANCES.

     The Construction Agent shall deliver to the Agent a requisition (a
"Requisition"), in the form attached hereto as EXHIBIT A or in such other form
as is satisfactory to the Agent, in its reasonable discretion, in connection
with (a) the Transaction Expenses and other fees, expenses and disbursements
payable, pursuant to Section 7.1, by the Lessor and (b) each Acquisition Advance
pursuant to Section 5.3 and (c) each Construction Advance pursuant to Section
5.4.


            SECTION 5.  FUNDING OF ADVANCES; CONDITIONS PRECEDENT;
                  REPORTING REQUIREMENTS ON COMPLETION DATE;
           THE LESSEE'S DELIVERY OF NOTICES; RESTRICTIONS ON LIENS.

     5.1. GENERAL.

          (a) To the extent funds have been advanced to the Lessor as Loans by
     the Lenders and to the Lessor as Holder Advances by the Holders, the Lessor
     will use such funds from time to time in accordance with the terms and
     conditions of this Agreement and the other Operative Agreements (i) at the
     direction of the Construction Agent to acquire the Properties in accordance
     with the terms of this Agreement, the Agency Agreement and the other
     Operative Agreements, (ii) to make Advances to the 

                                       4
<PAGE>
 
     Construction Agent to permit the acquisition, testing, engineering,
     installation, development, construction, modification, design, and
     renovation, as applicable, of the Properties (or components thereof) in
     accordance with the terms of the Agency Agreement and the other Operative
     Agreements, and (iii) to pay Transaction Expenses, fees, expenses and other
     disbursements payable by the Lessor under Sections 7.1(a) and 7.1(b).

          (b) In lieu of the payment of interest on the Loans and Holder Yield
     on the Holder Advances on any Scheduled Interest Payment Date with respect
     to any Property during the period prior to the Rent Commencement Date with
     respect to such Property, (i) each Lender's Loan shall automatically be
     increased by the amount of interest accrued and unpaid on such Loan for
     such period (except to the extent that at any time such increase would
     cause such Lender's Loan to exceed such Lender's Available Commitment, in
     which case the Lessee shall pay such excess amount to such Lender in
     immediately available funds on the date such Lender's Available Commitment
     was exceeded), and (ii) each Holder's Holder Advance shall automatically be
     increased by the amount of Holder Yield accrued and unpaid on such Holder
     Advance for such period (except to the extent that at any time such
     increase would cause the Holder Advance of such Holder to exceed such
     Holder's Available Holder Commitment, in which case the Lessee shall pay
     such excess amount to such Holder in immediately available funds on the
     date the Available Holder Commitment of such Holder was exceeded). Such
     increases in a Lender's Loan and a Holder's Holder Advance shall occur
     without any disbursement of funds by any Person.

     5.2. PROCEDURES FOR FUNDING.

          (a) The Construction Agent shall designate the date for Advances
     hereunder in accordance with the terms and provisions hereof; provided,
     however, it is understood and agreed that no more than two (2) Advances
     (excluding any conversion and/or continuation of any Loan or Holder
     Advance) may be requested during any calendar month; provided, further,
     each such Advance shall include all disbursements made on a given day under
     any Requisition and may relate to one or more Properties.  Not less than
     (i) three (3) Business Days prior to the Initial Closing Date and (ii)
     three (3) Business Days prior to the date on which any Acquisition Advance
     or Construction Advance is to be made, the Construction Agent shall deliver
     to the Agent, (A) with respect to the Initial Closing Date and each
     Acquisition Advance, a Requisition as described in Section 4.2 hereof
     (including without limitation a legal description of the Land in the case
     of a Requisition for an Acquisition Advance for the acquisition of such
     Land), a schedule of the Improvements, if any, and a schedule of the
     Equipment, if any, acquired or to be acquired on such date, and a schedule
     of the Work, if any, to be performed, each of the foregoing in a form
     reasonably acceptable to the Agent) and (B) with respect to each
     Construction Advance, a Requisition identifying (among other things) the
     Property to which such Construction Advance relates.

                                       5
<PAGE>
 
          (b) Each Requisition shall:  (i) be irrevocable, (ii) request funds in
     an amount that is not in excess of the total aggregate of the Available
     Commitments plus the Available Holder Commitments at such time, and (iii)
     request that the Holders make Holder Advances and that the Lenders make
     Loans to the Lessor for the payment of Transaction Expenses, Property
     Acquisition Costs (in the case of an Acquisition Advance) or other Property
     Costs (in the case of a Construction Advance) that have previously been
     incurred or are to be incurred on the date of such Advance to the extent
     such were not subject to a prior Requisition, in each case as specified in
     the Requisition.

          (c) Subject to the satisfaction of the conditions precedent set forth
     in Sections 5.3 or 5.4, as applicable, on each Property Closing Date or the
     date on which the Construction Advance is to be made, as applicable, (i)
     the Lenders shall make Loans based on their respective Lender Commitments
     to the Lessor in an aggregate amount equal to ninety-seven percent (97%) of
     the Requested Funds specified in any Requisition, (ratably between the
     Tranche A Lenders and the Tranche B Lenders with the Tranche A Lenders
     funding eighty-five percent (85%) of the Requested Funds and the Tranche B
     Lenders funding twelve percent (12%) of the Requested Funds) up to an
     aggregate principal amount equal to the aggregate of the Available
     Commitments, (ii) each Holder shall make a Holder Advance based on its
     Holder Commitment in an amount such that the aggregate of all Holder
     Advances at such time shall be three percent (3%) of the balance of the
     Requested Funds specified in such Requisition, up to the aggregate advanced
     amount equal to the aggregate of the Available Holder Commitments; and
     (iii) the total amount of such Loans and Holder Advances made on such date
     shall (x) be used by the Lessor to pay Property Costs and/or Transaction
     Expenses within three (3) Business Days of the receipt by the Lessor of
     such Advance or (y) be advanced by the Lessor on the date of such Advance
     to the Construction Agent or the Lessee to pay Property Costs, as
     applicable. Notwithstanding that the Operative Agreements state that
     Advances shall be directed to the Lessor, each Advance shall in fact be
     directed to the Agent (for the benefit of the Lessor) and applied by the
     Agent (for the benefit of the Lessor) pursuant to the requirements imposed
     on the Lessor under the Operative Agreements.

          (d) With respect to an Advance obtained by the Lessor to pay for
     Property Costs and/or Transaction Expenses and not expended by the Lessor
     for such purpose on the date of such Advance, such amounts shall be held by
     the Lessor (or the Agent on behalf of the Lessor) until the applicable
     closing date or, if such closing date does not occur within three (3)
     Business Days of the date of the Lessor's receipt of such Advance, shall be
     applied regarding the applicable Advance to repay the Lenders and the
     Holders and, subject to the terms hereof, and of the Credit Agreement and
     the Trust Agreement, shall remain available for future Advances.  Any such
     amounts held by the Lessor (or the Agent on behalf of the Lessor) shall be
     subject to the lien of the Security Agreement.

          (e) All Operative Agreements which are to be delivered to the Lessor,
     the Agent, the Lenders or the Holders shall be delivered to the Agent, on
     behalf of the Lessor, the Agent, the Lenders or the Holders, and such items
     (except for Notes, 

                                       6
<PAGE>
 
     Certificates, Bills of Sale, the Ground Leases and chattel paper originals,
     with respect to which in each case there shall be only one original) shall
     be delivered with originals sufficient for the Lessor, the Agent, each
     Lender and each Holder. All other items which are to be delivered to the
     Lessor, the Agent, the Lenders or the Holders shall be delivered to the
     Agent, on behalf of the Lessor, the Agent, the Lenders or the Holders, and
     such other items shall be held by the Agent. To the extent any such other
     items are requested in writing from time to time by the Lessor, any Lender
     or any Holder, the Agent shall provide a copy of such item to the party
     requesting it.

          (f) Notwithstanding the completion of any closing under this Agreement
     pursuant to Sections 5.3 or 5.4, each condition precedent waived in
     connection with any such closing may be subsequently enforced by the Agent
     (unless such has been expressly waived in writing by the Agent).

     5.3. CONDITIONS PRECEDENT FOR  THE LESSOR, THE AGENT, THE LENDERS AND
          THE HOLDERS RELATING TO THE INITIAL CLOSING DATE AND THE ADVANCE OF
          FUNDS FOR THE ACQUISITION OF A PROPERTY.

    The obligations (i) on the Initial Closing Date of the Lessor, the Agent,
the Lenders and the Holders to enter into the transactions contemplated by this
Agreement, including without limitation the obligation to execute and deliver
the applicable Operative Agreements to which each is a party on the Initial
Closing Date, (ii) on the Initial Closing Date of the Holders to make Holder
Advances, and of the Lenders to make Loans in order to pay Transaction Expenses
and (iii) on a Property Closing Date for the purpose of providing funds to the
Lessor necessary to pay the Transaction Expenses and to acquire or ground lease
a Property (an "Acquisition Advance"), in each case (with regard to the
foregoing Sections 5.3(i), (ii) and (iii)) are subject to the satisfaction or
waiver of the following conditions precedent on or prior to the Initial Closing
Date or the applicable Property Closing Date, as the case may be (To the extent
such conditions precedent require the delivery of any agreement, certificate,
instrument, memorandum, legal or other opinion, appraisal, commitment, title
insurance commitment, lien report or any other document of any kind or type,
such shall be in form and substance satisfactory to the Agent, in its reasonable
judgment. Notwithstanding the foregoing, the obligations of each party shall not
be subject to any conditions contained in this Section 5.3 which are required to
be performed by such party.):

          (a) the correctness of the representations and warranties of the
     parties to this Agreement contained herein, in each of the other Operative
     Agreements and each certificate delivered pursuant to any Operative
     Agreement (including without limitation the Incorporated Representations
     and Warranties) on each such date;

          (b) the performance by the parties to this Agreement of their
     respective agreements contained herein and in the other Operative
     Agreements to be performed by them on or prior to each such date;

                                       7
<PAGE>
 
          (c) the Agent shall have received a fully executed counterpart copy of
     the Requisition, appropriately completed;

          (d) title to each such Property shall conform to the representations
     and warranties set forth in Section 6.2(l) hereof;

          (e) the Construction Agent shall have delivered to the Agent a good
     standing certificate for the Construction Agent in the state where each
     such Property is located, the Deed with respect to the Land and existing
     Improvements (if any), a copy of the Ground Lease (if any), and a copy of
     the Bill of Sale with respect to the Equipment (if any), respecting such of
     the foregoing as are being acquired or ground leased on each such date with
     the proceeds of the Loans and Holder Advances or which have been previously
     acquired or ground leased with the proceeds of the Loans and Holder
     Advances and such Land, existing Improvements (if any) and Equipment (if
     any) shall be located in an Approved State;

          (f) there shall not have occurred and be continuing any Default or
     Event of Default under any of the Operative Agreements and no Default or
     Event of Default under any of the Operative Agreements will have occurred
     after giving effect to the Advance requested by each such Requisition;

          (g) the Construction Agent shall have delivered to the Agent title
     insurance commitments to issue policies respecting each such Property in
     favor of the Lessor and the Agent from a title insurance company reasonably
     acceptable to the Agent, with such title exceptions thereto as are
     reasonably acceptable to the Agent;

          (h) the Construction Agent shall have delivered to the Agent an
     environmental site assessment respecting each such Property prepared by an
     independent recognized professional reasonably acceptable to the Agent;

          (i) the Construction Agent shall have delivered to the Agent a survey
     (with a flood hazard certification) respecting each such Property prepared
     by an independent recognized professional reasonably acceptable to the
     Agent;

          (j) unless such an opinion has previously been delivered with respect
     to a particular state, the Construction Agent shall have caused to be
     delivered to the Agent a legal opinion in the form attached hereto as
     EXHIBIT B or in such other form as is acceptable to the Agent with respect
     to local law real property issues respecting the state in which each such
     Property is located addressed to the Lessor, the Agent, the Lenders and the
     Holders, from counsel located in the state where each such Property is
     located, prepared by counsel reasonably acceptable to the Agent;

          (k)  [Intentionally Omitted]

                                       8
<PAGE>
 
          (l) the Construction Agent shall have delivered to the Agent invoices
     for, or other reasonably satisfactory evidence of, the various Transaction
     Expenses;

          (m) the Construction Agent shall have caused to be delivered to the
     Agent a Mortgage Instrument (in such form as is reasonably acceptable to
     the Agent, with revisions as necessary to conform to applicable state law),
     Lessor Financing Statements and Lender Financing Statements respecting each
     such Property, all fully executed and in recordable form;

          (n) the Lessee shall have delivered to the Agent with respect to each
     such Property a Lease Supplement and a memorandum (or short form lease)
     regarding the Lease and such Lease Supplement (such memorandum or short
     form lease to be in the form attached to the Lease as EXHIBIT B or in such
     other form as is reasonably acceptable to the Agent, with modifications as
     necessary to conform to applicable state law, and in form suitable for
     recording);

          (o) with respect to each Acquisition Advance, the sum of the Available
     Commitment plus the Available Holder Commitment (after deducting the
     Unfunded Amount, if any, and after giving effect to the Acquisition
     Advance) will be sufficient to pay all amounts payable therefrom;

          (p) if any such Property is subject to a Ground Lease, the
     Construction Agent shall have caused a lease memorandum (or short form
     lease) to be delivered to the Agent for such Ground Lease and, if requested
     by the Agent, a landlord waiver and a mortgagee waiver (in each case, in
     such form as is reasonably acceptable to the Agent);

          (q)  [Intentionally Omitted];

          (r) the Construction Agent shall have delivered to the Agent a
     preliminary Construction Budget for each such Property, if applicable;

          (s) the Construction Agent shall have provided evidence to the Agent
     of insurance with respect to each such Property as provided in the Lease;

          (t) the Construction Agent shall have caused an Appraisal regarding
     each such Property to be provided to the Agent from an appraiser reasonably
     satisfactory to the Agent until such time as Appraisals for Properties then
     subject to the Lease have been submitted to the Agent and evidence an
     aggregate value of all such Properties of at least the Base Amount;

          (u) the Construction Agent shall cause (i) Uniform Commercial Code
     lien searches, tax lien searches and judgment lien searches regarding the
     Lessee to be conducted (and copies thereof to be delivered to the Agent) in
     such jurisdictions as reasonably determined by the Agent by a nationally
     recognized search company reasonably acceptable to the Agent and (ii) the
     liens referenced in such lien searches 

                                       9
<PAGE>
 
     which are objectionable to the Agent to be either removed or otherwise
     handled in a manner reasonably satisfactory to the Agent;

          (v) all taxes, fees and other charges in connection with the
     execution, delivery, recording, filing and registration of the Operative
     Agreements and/or documents related thereto shall have been paid or
     provisions for such payment shall have been made to the reasonable
     satisfaction of the Agent;

          (w) in the opinion of the Agent and its respective counsel, the
     transactions contemplated by the Operative Agreements do not and will not
     subject the Lessor, the Lenders, the Agent or the Holders to any adverse
     regulatory prohibitions, constraints, penalties or fines;

          (x) each of the Operative Agreements to be entered into on such date
     shall have been duly authorized, executed and delivered by the parties
     thereto, and shall be in full force and effect, and the Agent shall have
     received a fully executed copy of each of the Operative Agreements;

          (y) since the date of the most recent audited financial statements of
     AOR delivered pursuant to Section 5.1(b) of the Lessee Credit Agreement,
     there shall not have occurred any event, condition or state of facts which
     shall have or could reasonably be expected to have a Material Adverse
     Effect, other than as specifically contemplated by the Operative
     Agreements;

          (z) as of the Initial Closing Date only, the Agent shall have received
     an Officer's Certificate, dated as of the Initial Closing Date, of the
     Lessee in the form attached hereto as EXHIBIT D or in such other form as is
     reasonably acceptable to the Agent stating that (i) each and every
     representation and warranty of each Credit Party contained in the Operative
     Agreements to which it is a party is true and correct on and as of the
     Initial Closing Date; (ii) no Default or Event of Default has occurred and
     is continuing under any Operative Agreement; and (iii) each Operative
     Agreement to which any Credit Party is a party is in full force and effect
     with respect to it;

          (aa) as of the Initial Closing Date only, the Agent shall have
     received (i) a certificate of the Secretary or an Assistant Secretary of
     each Credit Party, dated as of the Initial Closing Date, in the form
     attached hereto as EXHIBIT E or in such other form as is reasonably
     acceptable to the Agent attaching and certifying as to (1) the resolutions
     of the Board of Directors of such Credit Party duly authorizing the
     execution, delivery and performance by such Credit Party of each of the
     Operative Agreements to which it is or will be a party, (2) the articles of
     incorporation of such Credit Party certified as of a recent date by the
     Secretary of State of its state of incorporation and its by-laws and (3)
     the incumbency and signature of persons authorized to execute and deliver
     on behalf of such Credit Party the Operative Agreements to which it is or
     will be a party and (ii) a good standing certificate (or local equivalent)
     from the appropriate office of the respective states where such Credit
     Party is incorporated and where the principal place of 

                                       10
<PAGE>
 
     business of such Credit Party is located as to its good standing in each
     such state (To the extent any Credit Party is a partnership, a limited
     liability company or is otherwise organized, such Credit Party shall
     deliver to the Agent (in form and substance reasonably satisfactory to the
     Agent) as of the Initial Closing Date (A) a certificate regarding such
     Credit Party and any corporate general partners covering the matters
     described in EXHIBIT E and (B) a good standing certificate, a certificate
     of limited partnership or a local equivalent of either of the foregoing, as
     applicable.);

          (bb) as of the Initial Closing Date only, the Agent shall have
     received an Officer's Certificate of the Lessor dated as of the Initial
     Closing Date in the form attached hereto as EXHIBIT F or in such other form
     as is reasonably acceptable to the Agent, stating that (i) each and every
     representation and warranty of the Lessor contained in the Operative
     Agreements to which it is a party is true and correct on and as of the
     Initial Closing Date, (ii) each Operative Agreement to which the Lessor is
     a party is in full force and effect with respect to it and (iii) the Lessor
     has duly performed and complied with all covenants, agreements and
     conditions contained herein or in any Operative Agreement required to be
     performed or complied with by it on or prior to the Initial Closing Date;

          (cc) as of the Initial Closing Date only, the Agent shall have
     received (i) a certificate of the Secretary, an Assistant Secretary, Trust
     Officer or Vice President of the Trust Company in the form attached hereto
     as EXHIBIT G or in such other form as is reasonably acceptable to the
     Agent, attaching and certifying as to (A) the signing resolutions duly
     authorizing the execution, delivery and performance by the Lessor of each
     of the Operative Agreements to which it is or will be a party, (B) its
     articles of association or other equivalent charter documents and its by-
     laws, as the case may be, certified as of a recent date by an appropriate
     officer of the Trust Company and (C) the incumbency and signature of
     persons authorized to execute and deliver on its behalf the Operative
     Agreements to which it is a party and (ii) a good standing certificate from
     the Office of the Comptroller of the Currency;

          (dd) as of the Initial Closing Date only, counsel for the Lessor
     reasonably acceptable to the Agent shall have issued to the Lessee, the
     Holders, the Lenders and the Agent its opinion in the form attached hereto
     as EXHIBIT H or in such other form as is reasonably acceptable to the
     Agent;

          (ee) as of the Initial Closing Date only, the Construction Agent shall
     have caused to be delivered to the Agent a legal opinion in the form
     attached hereto as EXHIBIT I or in such other form as is reasonably
     acceptable to the Agent, addressed to the Lessor, the Agent, the Lenders
     and the Holders, from counsel reasonably acceptable to the Agent; and

          (ff) as of the Initial Closing Date only, the Construction Agent shall
     cause (i) tax lien searches and judgment lien searches regarding each
     Credit Party to be conducted (and copies thereof to be delivered to the
     Agent) in such jurisdictions as determined by the Agent by a nationally
     recognized search company acceptable to the Agent and (ii) the 

                                       11
<PAGE>
 
     liens referenced in such lien searches which are objectionable to the Agent
     to be either removed or otherwise handled in a manner satisfactory to the
     Agent; provided this Section 5.3(ff) shall not be interpreted to limit or
     to contradict the requirements of Section 5.3(u).

     5.4. CONDITIONS PRECEDENT FOR THE LESSOR, THE AGENT, THE LENDERS AND
          THE HOLDERS RELATING TO THE ADVANCE OF FUNDS AFTER THE ACQUISITION
          ADVANCE.

     The obligations of the Holders to make Holder Advances, and the Lenders to
make Loans in connection with all requests for Advances subsequent to the
acquisition of a Property (and to pay the Transaction Expenses in connection
therewith) are subject to the satisfaction or waiver of the following conditions
precedent (To the extent such conditions precedent require the delivery of any
agreement, certificate, instrument, memorandum, legal or other opinion,
appraisal, commitment, title insurance commitment, lien report or any other
document of any kind or type, such shall be in form and substance satisfactory
to the Agent, in its reasonable discretion. Notwithstanding the foregoing, the
obligations of each party shall not be subject to any conditions contained in
this Section 5.4 which are required to be performed by such party.):

          (a) the correctness on such date of the representations and warranties
     of the parties to this Agreement contained herein, in each of the other
     Operative Agreements and each certificate delivered pursuant to any
     Operative Agreement (including without limitation the Incorporated
     Representations and Warranties);

          (b) the performance by the parties to this Agreement of their
     respective agreements contained herein and in the other Operative
     Agreements to be performed by them on or prior to each such date;

          (c) the Agent shall have received a fully executed counterpart of the
     Requisition, appropriately completed;

          (d) based upon the applicable Construction Budget which shall satisfy
     the requirements of this Agreement, the Available Commitments and the
     Available Holder Commitment (after deducting the Unfunded Amount) will be
     sufficient to complete the Improvements;

          (e) there shall not have occurred and be continuing any Default or
     Event of Default under any of the Operative Agreements and no Default or
     Event of Default under any of the Operative Agreements will have occurred
     after giving effect to the Construction Advance requested by the applicable
     Requisition;

          (f) the title insurance policy delivered in connection with the
     requirements of Section 5.3(g) shall provide for (or shall be endorsed to
     provide for) insurance in an amount at least equal to the maximum total
     Property Cost indicated by the Construction Budget referred to in
     subparagraph (d) above and there shall be no title change or exception
     objectionable to the Agent;

                                       12
<PAGE>
 
          (g) the Construction Agent shall have delivered to the Agent copies of
     the Plans and Specifications for the applicable Improvements;

          (h) the Construction Agent shall have delivered to the Agent invoices
     for, or other reasonably satisfactory evidence of, any Transaction Expenses
     and other fees, expenses and disbursements referenced in Section 7.1(b)
     that are to be paid with the Advance;

          (i) the Construction Agent shall have delivered, or caused to be
     delivered to the Agent, copies of invoices, Bills of Sale or other
     documents reasonably acceptable to the Agent, in each case with regard to
     any Equipment or other components of such Property then being acquired with
     the proceeds of the Loans and Holder Advances and naming the Lessor as
     purchaser and transferee;

          (j) all taxes, fees and other charges in connection with the
     execution, delivery, recording, filing and registration of the Operative
     Agreements shall have been paid or provisions for such payment shall have
     been made to the reasonable satisfaction of the Agent;

          (k) since the date of the most recent audited  Financial Statements
     (as such term is defined in the Lessee Credit Agreement) of the Lessee,
     there shall not have occurred any event, condition or state of facts which
     shall have or could reasonably be expected to have a Material Adverse
     Effect, other than as specifically contemplated by the Operative
     Agreements; and

          (l) in the opinion of the Agent and its counsel, the transactions
     contemplated by the Operative Agreements do not and will not subject the
     Lessor, the Lenders, the Agent or the Holders to any adverse regulatory
     prohibitions, constraints, penalties or fines arising out of any change in,
     or re-interpretation of, law or regulation since the Initial Closing Date.

     5.5. ADDITIONAL REPORTING AND DELIVERY REQUIREMENTS ON COMPLETION DATE
          AND ON CONSTRUCTION PERIOD TERMINATION DATE.

     Within 10 days after the Completion Date (but in no event later than the
Construction Period Termination Date) for each Property, the Construction Agent
shall deliver to the Agent an Officer's Certificate in the form attached hereto
as EXHIBIT J or in such other form as is reasonably acceptable to the Agent
specifying (a) the address for such Property, (b) the Completion Date for such
Property, (c) the aggregate Property Cost for such Property and (d) detailed,
itemized documentation supporting the asserted Property Cost figures. The Agent
shall have the right to contest on reasonable grounds the information contained
in such Officer's Certificate. Furthermore, on or prior to the Completion Date
for each Property, the Construction Agent shall deliver or cause to be delivered
to the Agent (unless previously delivered to the Agent) originals of the
following, each of which shall be in form and substance acceptable to the 

                                       13
<PAGE>
 
Agent, in its reasonable judgment: (u) a title insurance endorsement regarding
the title insurance policy delivered in connection with the requirements of
Section 5.3(g), but only to the extent such endorsement is necessary to provide
for insurance in an amount at least equal to the maximum total Property Cost
and, if endorsed, the endorsement shall not include a title change or exception
objectionable to the Agent; (v) an as-built survey for such Property, (w)
insurance certificates respecting such Property as required hereunder and under
the Lease Agreement, (x) a memorandum (or short form) of the Lease and such
Lease Supplement (in form suitable for recording) and (y) if requested by the
Agent, amendments to the Lessor Financing Statements executed by the appropriate
parties. In addition, on the Completion Date for such Property the Construction
Agent covenants and agrees that the recording fees, documentary stamp taxes or
similar amounts required to be paid in connection with the related Mortgage
Instrument shall be or have been paid in an amount required by applicable law,
subject, however, to the obligations of the Lenders and the Holders to fund such
costs to the extent required pursuant to Section 7.1.

    5.6. THE CONSTRUCTION AGENT DELIVERY OF CONSTRUCTION BUDGET
          MODIFICATIONS.

     The Construction Agent covenants and agrees to deliver to the Agent each
month notification of any modification to any Construction Budget regarding any
Property if such modification materially increases the cost to construct such
Property; provided, no Construction Budget may be increased unless (a) the title
insurance policies referenced in Section 5.3(g) are also modified or endorsed,
if necessary, to provide for insurance in an amount that satisfies the
requirements of Section 5.4(f) of this Agreement and (b) after giving effect to
any such amendment, the Construction Budget remains in compliance with the
requirements of Section 5.4(d) of this Agreement.

     5.7. RESTRICTIONS ON LIENS.

     On each Property Closing Date, the Construction Agent shall cause each
Property acquired by the Lessor on such date to be free and clear of all Liens
except those referenced in Sections 6.2(r)(i) and 6.2(r)(ii). On each date a
Property is either sold to a third party in accordance with the terms of the
Operative Agreements or, pursuant to Section 22.1(a) of the Lease Agreement,
retained by the Lessor, the Lessee shall cause such Property to be free and
clear of all Liens (other than Lessor Liens and such other Liens that are
expressly set forth as title exceptions on the title commitment issued under
Section 5.3(g) with respect to such Property, to the extent such title
commitment has been approved by the Agent).

     5.8. ACCESSION AGREEMENT REQUIREMENTS - NEW TRANCHE A GUARANTORS.

     AOR and its Subsidiaries may from time to time create or acquire new
Subsidiaries, provided, that at any time promptly upon request by the Agent (and
in any event, with respect to any new Subsidiary that is created or acquired in
connection with a Physician Transaction or that is requested or required to
become a guarantor under the Lessee Credit Agreement prior to or concurrently
with satisfaction of the conditions set forth in clauses (y) and (z) of clause
(i) below or, if earlier, the consummation of such Physician Transaction), (i)
each such new Subsidiary (y) having assets with a gross value (determined in
accordance with GAAP) in excess of $100,000, 

                                       14
<PAGE>
 
and (z) having commenced the conduct of an active business, will execute and
deliver to the Agent (with sufficient copies for each Financing Party) an
Accession Agreement in the form of Exhibit K and such other documents to
effectuate the foregoing as may be reasonably requested by the Majority Secured
Parties, and (ii) AOR will cause each such new Subsidiary to execute and
deliver, and will cause to be delivered, all documentation of the type described
in Section 5.3 as such new Subsidiary would have had to deliver were it a
Tranche A Guarantor on the Initial Closing Date.

     5.9. MAINTENANCE OF AOR SYNTHETIC REAL ESTATE, INC. AS A WHOLLY-OWNED 
          ENTITY.

     From the Initial Closing Date and thereafter until such time as all
obligations of all Credit Parties under the Operative Agreements have been
satisfied and performed in full, AOR shall retain the Lessee as a Wholly-Owned
Entity of AOR.

     5.10.  POST-CLOSING REQUIREMENTS REGARDING CERTAIN PROPERTIES FOR
            WHICH ADVANCES ARE MADE ON THE INITIAL CLOSING DATE.

     With respect to all Properties to which the Owner Trustee holds title on or
prior to the Initial Closing Date and for which Advances are made on the Initial
Closing Date, within forty-five (45) days after the Initial Closing Date, and to
the extent not delivered with respect to the Initial Closing Date, the
Construction Agent shall deliver to the Agent any and all items specified in
Section 5.3 with respect to such Properties including without limitation surveys
(with flood hazard certificates), title insurance endorsements, appraisals and
opinions. All such items shall be in form and substance reasonably satisfactory
to the Agent.

     To the extent the requirements of Section 5.3 are not satisfied with
respect to such Properties within forty-five (45) days after the Initial Closing
Date, the Agent (upon direction from the Majority Secured Parties) may require
the Lessee to purchase, and the Agent shall purchase, all such Properties on a
Business Day specified by the Agent for an amount equal to the Termination Value
with respect to such Properties and otherwise in accordance with Sections 20.1
through 20.2 of the Lease (as if such date specified by the Agent were an
Election Date).

     Unless the Financing Parties otherwise agree, the Financing Parties shall
have no obligation to make any additional Advances with respect to such
Properties until such time as the requirements of Section 5.3 are satisfied with
respect to such Properties.

                  SECTION 6.  REPRESENTATIONS AND WARRANTIES.

     6.1. REPRESENTATIONS AND WARRANTIES OF THE BORROWER.

     Effective as of the Initial Closing Date, the date of each Advance and the
Rent Commencement Date, the Trust Company in its individual capacity and as the
Borrower, as indicated, represents and warrants to each of the other parties
hereto as follows, provided, that 

                                       15
<PAGE>
 
the representations in the following paragraphs (h), (j) and (k) are made solely
in its capacity as the Borrower:

          (a) It is a national banking association and is duly organized and
     validly existing and in good standing under the laws of the United States
     of America and has the power and authority to enter into and perform its
     obligations under the Trust Agreement and (assuming due authorization,
     execution and delivery of the Trust Agreement by the Holders) has the
     corporate and trust power and authority to act as the Owner Trustee and to
     enter into and perform the obligations under each of the other Operative
     Agreements to which the Trust Company or the Owner Trustee, as the case may
     be, is or will be a party and each other agreement, instrument and document
     to be executed and delivered by it on or before such Closing Date in
     connection with or as contemplated by each such Operative Agreement to
     which the Trust Company or the Owner Trustee, as the case may be, is or
     will be a party;

          (b) The execution, delivery and performance of each Operative
     Agreement to which it is or will be a party, either in its individual
     capacity or (assuming due authorization, execution and delivery of the
     Trust Agreement by the Holders) as the Owner Trustee, as the case may be,
     has been duly authorized by all necessary action on its part and neither
     the execution and delivery thereof, nor the consummation of the
     transactions contemplated thereby, nor compliance by it with any of the
     terms and provisions thereof (i) does or will require any approval or
     consent of any trustee or holders of any of its indebtedness or
     obligations, (ii) does or will contravene any Legal Requirement, (iii) does
     or will contravene or result in any breach of or constitute any default
     under, or result in the creation of any Lien upon any of its property
     under, (A) its charter or by-laws, or (B) any indenture, mortgage, chattel
     mortgage, deed of trust, conditional sales contract, bank loan or credit
     agreement or other agreement or instrument to which it is a party or by
     which it or its properties may be bound or affected, which contravention,
     breach, default or Lien under clause (B) would materially and adversely
     affect its ability, in its individual capacity or as the Owner Trustee, to
     perform its obligations under the Operative Agreements to which it is a
     party or (iv) does or will require any Governmental Action by any
     Governmental Authority;

          (c) The Trust Agreement and, assuming the Trust Agreement is the
     legal, valid and binding obligation of the Holders, each other Operative
     Agreement to which the Trust Company or the Owner Trustee, as the case may
     be, is or will be a party have been, or on or before such Closing Date will
     be, duly executed and delivered by the Trust Company or the Owner Trustee,
     as the case may be, and the Trust Agreement and each such other Operative
     Agreement to which the Trust Company or the Owner Trustee, as the case may
     be, is a party constitutes, or upon execution and delivery will constitute,
     a legal, valid and binding obligation enforceable against the Trust Company
     or the Owner Trustee, as the case may be, in accordance with the terms
     thereof;

          (d) There is no action or proceeding pending or, to its knowledge,
     threatened to which it is or will be a party, either in its individual
     capacity or as the Owner Trustee, 

                                       16
<PAGE>
 
     before any Governmental Authority that, if adversely determined, would
     materially and adversely affect its ability, in its individual capacity or
     as the Owner Trustee, to perform its obligations under the Operative
     Agreements to which it is a party or would question the validity or
     enforceability of any of the Operative Agreements to which it is or will
     become a party;

          (e) It has not assigned or transferred any of its right, title or
     interest in or under the Lease, the Agency Agreement or its interest in any
     Property or any portion thereof, except in accordance with the Operative
     Agreements;

          (f) No Default of Event of Default under the Operative Agreements
     attributable to it has occurred and is continuing;

          (g) Except as otherwise contemplated in the Operative Agreements, the
     proceeds of the Loans and Holder Advances shall not be applied by the Owner
     Trustee for any purpose other than the repayment of the Bridge Financing,
     the purchase and/or lease of the Properties, the acquisition, installation
     and testing of the Equipment, the construction of Improvements and the
     payment of Transaction Expenses, in each case which accrue prior to the
     Rent Commencement Date with respect to a particular Property and in each
     case in accordance with the Agency Agreement;

          (h) Neither the Owner Trustee nor any Person authorized by the Owner
     Trustee to act on its behalf has offered or sold any interest in the Trust
     Estate or the Notes, or in any similar security relating to a Property, or
     in any security the offering of which for the purposes of the Securities
     Act would be deemed to be part of the same offering as the offering of the
     aforementioned securities to, or solicited any offer to acquire any of the
     same from, any Person other than, in the case of the Notes, the Agent, and
     neither the Owner Trustee nor any Person authorized by the Owner Trustee to
     act on its behalf will take any action which would subject, as a direct
     result of such action alone, the issuance or sale of any interest in the
     Trust Estate or the Notes to the provisions of Section 5 of the Securities
     Act or require the qualification of any Operative Agreement under the Trust
     Indenture Act of 1939, as amended;

          (i) The Owner Trustee's principal place of business, chief executive
     office and office where the documents, accounts and records relating to the
     transactions contemplated by this Agreement and each other Operative
     Agreement are kept are located at 79 South Main Street, Salt Lake City,
     Utah 84111;

          (j) The Owner Trustee is not engaged principally in, and does not have
     as one (1) of its important activities, the business of extending credit
     for the purpose of purchasing or carrying any margin stock (within the
     meaning of Regulation U of the Board of Governors of the Federal Reserve
     System of the United States), and no part of the proceeds of the Loans or
     the Holder Advances will be used by it to purchase or carry any margin
     stock or to extend credit to others for the purpose of purchasing or
     carrying any such margin stock or for any purpose that violates, or is
     inconsistent with, the 

                                       17
<PAGE>
 
     provisions of Regulations G, T, U, or X of the Board of Governors of the
     Federal Reserve System of the United States;

          (k) The Owner Trustee is not an "investment company" or a company
     controlled by an "investment company" within the meaning of the Investment
     Company Act;

          (l) Each Property is free and clear of all Lessor Liens attributable
     to the Owner Trustee in its individual capacity; and

          (m) The Owner Trustee, in its trust capacity, is a party to no
     documents, instruments or agreements other than documents in connection
     with the Bridge Financing and the Operative Agreements to which it is a
     party and any other documents delivered by the Owner Trustee in connection
     with the Operative Agreements.

Effective as of the Initial Closing Date, the date of each Advance and the Rent
Commencement Date, the Owner Trustee represents and warrants that each Property
is free and clear of all Lessor Liens.

     6.2. REPRESENTATIONS AND WARRANTIES OF EACH CREDIT PARTY.

     Effective as of the Initial Closing Date, the date of each Advance, the
date each Wholly-Owned Entity delivers an Accession Agreement and the Rent
Commencement Date, each Credit Party represents and warrants to each of the
other parties hereto that:

          (a) The Incorporated Representations and Warranties are true and
     correct (unless such relate solely to an earlier point in time) and the
     Lessee has delivered to the Agent the financial statements and other
     reports referred to in Section 5.1 of the Lessee Credit Agreement;

          (b) The execution and delivery by each Credit Party of this Agreement
     and the other applicable Operative Agreements as of such date and the
     performance by each Credit Party of its respective obligations under this
     Agreement and the other applicable Operative Agreements are within the
     corporate, partnership or limited liability company (as the case may be)
     powers of each Credit Party, have been duly authorized by all necessary
     corporate, partnership or limited liability company (as the case may be)
     action on the part of each Credit Party (including without limitation any
     necessary shareholder, partnership or limited liability company action),
     have been duly executed and delivered, have received all necessary
     governmental approval required to be obtained by each Credit Party, and do
     not and will not (i) violate any Legal Requirement which is binding on any
     Credit Party or any of their Subsidiaries, (ii) contravene or conflict
     with, or result in a breach of, any provision of (A) the Articles of
     Incorporation, By-Laws or other organizational documents of any Credit
     Party or any of their Subsidiaries or (B) any agreement, indenture,
     instrument or other document which is binding on any Credit Party or any of
     their Subsidiaries (excepting such contravention of, conflict with or
     breach 

                                       18
<PAGE>
 
     thereof which shall not have or could not reasonably be expected to have a
     Material Adverse Effect) or (iii) result in, or require, the creation or
     imposition of any Lien (other than pursuant to the terms of the Operative
     Agreements) on any asset of any Credit Party or any of their Subsidiaries;

          (c) This Agreement and the other applicable Operative Agreements to
     which any Credit Party is a party, executed prior to and as of such date,
     constitute the legal, valid and binding obligation of each Credit Party, as
     applicable, enforceable against each Credit Party, as applicable, in
     accordance with their terms, except as enforceability may be limited by
     applicable bankruptcy, insolvency, reorganization, moratorium or other
     similar laws affecting creditor's rights generally or by general principles
     of equity.  Each Credit Party has executed the various Operative Agreements
     required to be executed as of such date;

          (d) Except as described in EXHIBIT L, there are no material actions,
     suits or proceedings pending or, to the knowledge of any Credit Party,
     threatened against any Credit Party in any court or before any Governmental
     Authority (nor shall any order, judgment or decree have been issued or to
     the knowledge of any Credit Party, proposed to be issued by any
     Governmental Authority to set aside, restrain, enjoin or prevent the full
     performance of any Operative Agreement or any transaction contemplated
     thereby) that (i) concern any Property or any Credit Party's interest
     therein,  (ii) question the validity or enforceability of any Operative
     Agreement or any transaction contemplated by the Operative Agreements or
     (iii) shall have or could reasonably be expected to have a Material Adverse
     Effect;

          (e) No Governmental Action by any Governmental Authority or other
     authorization, registration, consent, approval, waiver, notice or other
     action by, to or of any other Person (x) pursuant to any Legal Requirement
     or (y) pursuant to any contract, indenture, instrument or agreement (the
     failure of which to obtain in the case of this clause (y) shall not have or
     could not reasonably be expected to have a Material Adverse Effect) is
     required to have been obtained on the part of any Credit Party to authorize
     or is required in connection with (i) the execution, delivery or
     performance of any Operative Agreement, (ii) the legality, validity,
     binding effect or enforceability of any Operative Agreement, (iii) the
     acquisition, ownership, construction, completion, occupancy, operation,
     leasing or subleasing of any Property except for those that may
     appropriately be obtained at a later date or (iv) any Advance, in each
     case, except those which have been obtained and are in full force and
     effect;

          (f) Upon the execution and delivery of each Lease Supplement to the
     Lease, (i) the Lessee will have unconditionally accepted the Property
     subject to the Lease Supplement and will have a valid and subsisting
     leasehold interest in such Property, subject only to the Permitted Liens,
     and (ii) no offset will exist with respect to any Rent or other sums
     payable under the Lease;

                                       19
<PAGE>
 
          (g) Except as otherwise contemplated by the Operative Agreements, the
     Construction Agent shall not use the proceeds of any Holder Advance or Loan
     for any purpose other than the purchase and/or lease of the Properties, the
     acquisition, installation and testing of the Equipment, the construction of
     Improvements and the payment of Transaction Expenses, in each case which
     accrue prior to the Rent Commencement Date with respect to a particular
     Property;

          (h) All information heretofore or contemporaneously herewith furnished
     by any Credit Party or any of their Subsidiaries to the Agent, the Owner
     Trustee, any Lender or any Holder for purposes of or in connection with
     this Agreement and the transactions contemplated hereby is, and all
     information hereafter furnished by or on behalf of any Credit Party or any
     of their Subsidiaries to the Agent, the Owner Trustee, any Lender or any
     Holder pursuant hereto or in connection herewith will be, true and accurate
     in all material respects on the date as of which such information is dated
     or certified, and such information, taken as a whole, does not and will not
     omit to state any material fact necessary to make such information, taken
     as a whole, not misleading;

          (i) The Lessee is duly incorporated under the laws of the State of
     Delaware.  The principal place of business, chief executive office and
     office of the Construction Agent and the Lessee where the documents,
     accounts and records relating to the transactions contemplated by this
     Agreement and each other Operative Agreement are kept are located at
     Houston, Harris County, Texas.  The states of incorporation/formation and
     the principal place of business of the Tranche A Guarantors are located in
     the states set forth in EXHIBIT M;

          (j) The representations and warranties of each Credit Party set forth
     in any of the Operative Agreements are true and correct in all material
     respects on and as of each such date as if made on and as of such date
     (unless expressly referring to another date and in each case, such
     representations and warranties shall have been true and correct on and as
     of such earlier date). There exists no Default or Event of Default under
     any of the Operative Agreements which is continuing and which has not been
     cured within any cure period expressly granted under the terms of the
     applicable Operative Agreement or otherwise waived in accordance with the
     applicable Operative Agreement.  No Default or Event of Default will occur
     under any of the Operative Agreements as a result of, or after giving
     effect to, the Advance requested by the Requisition on the date of such
     Advance;

          (k) As of each Property Closing Date and the date of each subsequent
     Advance and the Rent Commencement Date only, each Property then being
     financed consists of (i) unimproved Land or (ii) Land and existing
     Improvements thereon which Improvements are either suitable for occupancy
     at the time of acquisition, ground leasing or at the Rent Commencement Date
     or will be renovated and/or modified in accordance with the terms of this
     Agreement on or prior to the Rent Commencement Date.  Each Property then
     being financed is located at the location set forth on the applicable
     Requisition, each of which is in one (1) of the Approved States;

                                       20
<PAGE>
 
          (l) As of each Property Closing Date, the date of each subsequent
     Advance and the Rent Commencement Date only, the Lessor has good and
     indefeasible fee simple title to each Property, or, if any Property is the
     subject of a Ground Lease, the Lessor will have a valid ground leasehold
     interest enforceable against the ground lessor of such Property in
     accordance with the terms of such Ground Lease, subject only to (i) such
     Liens referenced in Sections 6.2(r)(i) and 6.2(r)(ii) on the applicable
     Property Closing Date and (ii) subject to Section 5.7, Permitted Liens
     after the applicable Property Closing Date;

          (m) As of each Property Closing Date, the date of each subsequent
     Advance and the Rent Commencement Date only, no portion of any Property is
     located in an area identified as a special flood hazard area by the Federal
     Emergency Management Agency or other applicable agency, or if any such
     Property is located in an area identified as a special flood hazard area by
     the Federal Emergency Management Agency or other applicable agency, then
     flood insurance has been obtained for such Property in accordance with
     Section 14.2(b) of the Lease and in accordance with the National Flood
     Insurance Act of 1968, as amended;

          (n) As of each Property Closing Date, the date of each subsequent
     Advance and the Rent Commencement Date only, each Property complies with
     all Insurance Requirements and in all material respects with all standards
     of the Credit Parties with respect to similar properties owned by any
     Credit Party;

          (o) As of each Property Closing Date, the date of each subsequent
     Advance and the Rent Commencement Date only, each Property complies with
     all Legal Requirements as of such date (including without limitation all
     zoning and land use laws and Environmental Laws), except to the extent that
     failure to comply therewith, individually or in the aggregate, shall not
     have and could not reasonably be expected to have a Material Adverse
     Effect;

          (p) As of each Property Closing Date, the date of each subsequent
     Advance and the Rent Commencement Date only, all utility services and
     facilities necessary for the construction and operation of the Improvements
     and the installation and operation of the Equipment regarding each Property
     (including without limitation gas, electrical, water and sewage services
     and facilities) are available at the applicable Land and will be
     constructed prior to the Completion Date for such Property;

          (q) As of each Property Closing Date, the date of each subsequent
     Advance and the Rent Commencement Date only, acquisition, installation and
     testing of the Equipment (if any) and construction of the Improvements (if
     any) to such date shall have been performed in a good and workmanlike
     manner, substantially in accordance with the applicable Plans and
     Specifications;

          (r)  (i)  The Security Documents create, as security for the
     Obligations (as such term is defined in the Security Agreement), valid and
     enforceable security interests 

                                       21
<PAGE>
 
     in, and Liens on, all of the Collateral, in favor of the Agent, for the
     ratable benefit of the Lenders and the Holders, as their respective
     interests appear in the Operative Agreements, and such security interests
     and Liens are subject to no other Liens (subject to Liens for Taxes not yet
     due and payable) other than Liens that are expressly set forth as title
     exceptions on the title commitment issued under Section 5.3(g) with respect
     to the applicable Property, to the extent such title commitment has been
     approved by the Agent. Upon recordation of the Mortgage Instrument in the
     real estate recording office in the applicable Approved State identified by
     the Construction Agent or the Lessee, the Lien created by the Mortgage
     Instrument in the real property described therein shall be a perfected
     first priority mortgage Lien on such real property in favor of the Agent,
     for the ratable benefit of the Lenders and the Holders, as their respective
     interests appear in the Operative Agreements subject to no other Liens
     (subject to Liens for Taxes not yet due and payable) other than Liens that
     are expressly set forth as title exceptions on the title commitment issued
     under Section 5.3(g) with respect to the applicable Property, to the extent
     such title commitment has been approved by the Agent. To the extent that
     the security interests in the portion of the Collateral comprised of
     personal property can be perfected by filing in the filing offices in the
     applicable Approved States or elsewhere identified by the Construction
     Agent or the Lessee, upon filing of the Lender Financing Statements in such
     filing offices, the security interests created by the Security Agreement
     shall be perfected first priority security interests (subject to Liens for
     Taxes not yet due and payable) in such personal property in favor of the
     Agent, for the ratable benefit of the Lenders and the Holders, as their
     respective interests appear in the Operative Agreements to the extent that
     perfection may be accomplished by the filing of financing statements;

          (ii) The Lease Agreement creates, as security for the obligations of
     the Lessee under the Lease Agreement, valid and enforceable security
     interests in, and Liens on, each Property leased thereunder, in favor of
     the Lessor, and such security interests and Liens are subject to no other
     Liens (subject to Liens for Taxes not yet due and payable) other than Liens
     that are expressly set forth as title exceptions on the title commitment
     issued under Section 5.3(g) with respect to the applicable Property, to the
     extent such title commitment has been approved by the Agent.  Upon
     recordation of the memorandum of the Lease Agreement and the memorandum of
     a Ground Lease (or, in either case, a short form lease) in the real estate
     recording office in the applicable Approved State identified by the
     Construction Agent or the Lessee, the Lien created by the Lease Agreement
     in the real property described therein shall be a perfected first priority
     mortgage Lien (subject to Liens for Taxes not yet due and payable) on such
     real property in favor of the Agent, for the ratable benefit of the Lenders
     and the Holders, as their respective interests 

                                       22
<PAGE>
 
     appear in the Operative Agreements. To the extent that the security
     interests in the portion of any Property comprised of personal property can
     be perfected by the filing in the filing offices in the applicable Approved
     State or elsewhere identified by the Construction Agent or the Lessee upon
     filing of the Lessor Financing Statements in such filing offices, a
     security interest created by the Lease Agreement shall be a perfected first
     priority security interest (subject to Liens for Taxes not yet due and
     payable) in such personal property in favor of the Lessor, which rights
     pursuant to the Lessor Financing Statements are assigned to the Agent, for
     the ratable benefit of the Lenders and the Holders, as their respective
     interests appear in the Operative Agreements to the extent perfection may
     be accomplished by the filing of financing statements;

          (s) The Plans and Specifications for each Property will be prepared
     prior to the commencement of construction in accordance with all applicable
     Legal Requirements (including without limitation all applicable
     Environmental Laws and building, planning, zoning and fire codes), except
     to the extent the failure to comply therewith, individually or in the
     aggregate, shall not have and could not reasonably be expected to have a
     Material Adverse Effect.  Upon completion of the Improvements for each
     Property in accordance with the applicable Plans and Specifications, such
     Improvements will be within any building restriction lines and will not
     encroach in any manner onto any adjoining land (except as permitted by
     express written easements, which have been approved by the Agent);

          (t) As of the Rent Commencement Date only, each Property shall be
     improved in accordance with the applicable Plans and Specifications in a
     good and workmanlike manner, shall be operational and shall constitute all
     the equipment, facilities, rights, other personal property and other real
     property necessary to operate, utilize and maintain such Property for its
     originally intended purpose in a commercially reasonable manner and on an
     independent, stand alone basis;

          (u) As of each Property Closing Date only, each Property has been
     acquired or ground leased pursuant to a Ground Lease at a price that is not
     in excess of fair market value or fair market rental value, as the case may
     be; and

          (v) As of the Initial Closing Date only, each Wholly-Owned Entity
     (formed or acquired prior to or on such date) shall have executed this
     Agreement and the Credit Agreement in its capacity as a Tranche A Guarantor
     and, as to AOR, in its capacity as the Guarantor and as a Tranche A
     Guarantor.


                    SECTION 7. PAYMENT OF CERTAIN EXPENSES.

     7.1. TRANSACTION EXPENSES.

          (a) The Lessor agrees on the Initial Closing Date, to pay, or cause to
     be paid, all Transaction Expenses arising from the Initial Closing Date,
     including without limitation all reasonable fees, expenses and
     disbursements of the various legal counsels for the Lessor and the Agent in
     connection with the transactions contemplated by the Operative Agreements
     and incurred in connection with such Initial Closing Date, the initial fees
     and expenses of the Owner Trustee due and payable on such Initial Closing
     Date, all fees, taxes and expenses for the recording, registration and
     filing of documents and all other reasonable fees, expenses and
     disbursements incurred in connection with such Initial Closing Date;
     provided, however, the Lessor shall pay such amounts described in this
     Section 7.1(a) only if (i) such amounts are properly described in a

                                       23
<PAGE>
 
     Requisition delivered on or before the Initial Closing Date, and (ii) funds
     are made available by the Lenders and the Holders in connection with such
     Requisition in an amount sufficient to allow such payment.  On the Initial
     Closing Date after delivery and receipt of the Requisition referenced in
     Section 4.2(a) hereof and satisfaction of the other conditions precedent
     for such date, the Holders shall make Holder Advances and the Lenders shall
     make Loans to the Lessor to pay for the Transaction Expenses.  The Lessee
     agrees to timely pay all amounts referred to in this Section 7.1(a) to the
     extent not paid by the Lessor.

          (b) Assuming no Default or Event of Default shall have occurred and be
     continuing and only for the period prior to the Rent Commencement Date, the
     Lessor agrees on each Property Closing Date, on the date of any
     Construction Advance and on the Completion Date to pay, or cause to be
     paid, all Transaction Expenses including without limitation all reasonable
     fees, expenses and disbursements of the various legal counsels for the
     Lessor and the Agent in connection with the transactions contemplated by
     the Operative Agreements and billed in connection with such Advance or such
     Completion Date, all Transaction Expenses arising from the Initial Closing
     Date which have not been previously paid by the Lessor, the annual fees and
     reasonable out-of-pocket expenses of the Owner Trustee, all fees, expenses
     and disbursements incurred with respect to the various items referenced in
     Sections 5.3, 5.4 and/or 5.5 (including without limitation any premiums for
     title insurance policies and charges for any updates to such policies), all
     other reasonable fees, expenses and disbursements in connection with such
     Advance or such Completion Date and all other Transaction Expenses
     theretofore incurred and not paid by the Lessor, including without
     limitation all expenses relating to and all fees, taxes and expenses for
     the recording, registration and filing of documents and during the
     Commitment Period, all fees, expenses and costs referenced in Sections
     7.3(a), 7.3(b), 7.3(d) and 7.4; provided, however, the Lessor shall pay
     such amounts described in this Section 7.1(b) on the applicable Business
     Day only if (i) such amounts are properly described in a Requisition
     delivered on the applicable date and (ii) funds are made available by the
     Lenders and the Holders in connection with such Requisition in an amount
     sufficient to allow such payment. On each Property Closing Date, on the
     date of any Construction Advance or any Completion Date, after delivery of
     the applicable Requisition and satisfaction of the other conditions
     precedent for such date, the Holders shall make a Holder Advance and the
     Lenders shall make Loans to the Lessor to pay for the Transaction Expenses
     referenced in this Section 7.1(b). The Lessee agrees to timely pay all
     amounts referred to in this Section 7.1(b) to the extent not paid by the
     Lessor.

     7.2. BROKERS' FEES.

     The Lessee agrees to pay or cause to be paid any and all brokers' fees, if
any, including without limitation any interest and penalties thereon, which are
payable in connection with the transactions contemplated by this Agreement and
the other Operative Agreements.

                                       24
<PAGE>
 
     7.3. CERTAIN FEES AND EXPENSES.

     The Lessee agrees to pay or cause to be paid (a) the initial and annual
Owner Trustee's fee and all reasonable expenses of the Owner Trustee and any co-
trustees (including without limitation reasonable counsel fees and expenses) or
any successor owner trustee and/or co-trustee, for acting as the owner trustee
under the Trust Agreement, (b) all reasonable out-of-pocket costs and expenses
incurred by the Credit Parties, the Agent, the Lenders, the Holders or the
Lessor in entering into any Lease Supplement and any future amendments,
modifications, supplements, restatements and/or replacements with respect to any
of the Operative Agreements, whether or not such Lease Supplement, amendments,
modifications, supplements, restatements and/or replacements are ultimately
entered into, or giving or withholding of waivers of consents hereto or thereto,
which have been requested by the Credit Parties, the Agent, the Lenders, the
Holders or the Lessor, (c) all reasonable out-of-pocket costs and expenses
incurred by the Construction Agent, the Lessee, the Agent, the Lenders, the
Holders or the Lessor in connection with any exercise of remedies under any
Operative Agreement or any purchase of any Property by the Construction Agent,
the Lessee or any third party and (d) all reasonable out-of-pocket costs and
expenses incurred by the Credit Parties, the Agent, the Lenders, the Holders or
the Lessor in connection with any transfer or conveyance of any Property,
whether or not such transfer or conveyance is ultimately accomplished.

     7.4. FACILITY FEE.

     Until the Maturity Date, the Lessee agrees to pay or to cause to be paid to
the Agent for the account of (a) the Lenders, respectively, a facility fee (the
"Lender Facility Fee") equal to the product of either (i) the average daily
Commitment of each Lender (for Tranche A Loans and Tranche B Loans) during the
Commitment Period or (ii) after the Commitment Period, the average daily
aggregate amount of the Advances of such Lender outstanding until the Maturity
Date, in each case multiplied by the applicable percentage set forth in the
matrix below per annum and (b) the Holders, respectively, a facility fee (the
"Holder Facility Fee") equal to the product of either (i) the average daily
Holder Commitment of each Holder during the Commitment Period or (ii) after the
Commitment Period, the average daily aggregate amount of the Advances of such
Holder outstanding until the Maturity Date, in each case multiplied by the
applicable percentage set forth in the matrix below per annum. From the Initial
Closing Date until the fifth (5th) day after delivery of the December 31, 1997
financial statements pursuant to Section 28.1 of the Lease, such applicable
percentage shall be 0.200% for both the Lender Facility Fee and for the Holder
Facility Fee. Such Facility Fees shall be calculated on the basis of a year of
three hundred sixty (360) days for the actual days elapsed and shall be payable
in arrears on the last Business Day of each fiscal quarter of the Lessee,
commencing with the fiscal quarter ending December 31, 1997. The Facility Fees
shall be reset from time to time at the time of the resetting of the Applicable
Margin. If all or a portion of any such Facility Fee shall not be paid when due,
such overdue amount shall bear interest, payable by the Lessee on demand, at a
rate per annum equal to the ABR (or in the case of Holder Yield, the ABR plus
the Applicable Margin for Eurodollar Holder Advances) plus two percent (2%) from
the date of such non-payment until such amount is paid in full (as well as
before judgment).

                                       25
<PAGE>
 
<TABLE>
<CAPTION>
 
  Ratio of Consolidated                Lender                Holder    
Debt to Annualized EBITDA           Facility Fee          Facility Fee 
-------------------------           ------------          ------------ 
<S>                                 <C>                   <C>          
                                                                       
                                                                       
                                                                       
Greater than 3.0 to 1.0                 0.250%                0.250%    
                                                                        
                                                                        
                                                                        
Greater than 2.0 to 1.0 but less        0.200%                0.200%    
 than or equal to 3.0 to 1.0                                            
                                                                        
                                                                        
                                                                        
Less than or equal to 2.0 to 1.0        0.175%                0.175%    
 
 
 
</TABLE>

     7.5. ADMINISTRATIVE FEE.

     During the Term, the Lessee agrees to pay or to cause to be paid to the
Agent (for the account of the Agent) the administrative fee contemplated by to
the terms of the engagement letter dated October 24, 1997, as supplemented from
time to time, from First Union Capital Markets Corp. to AOR.


                  SECTION 8.  OTHER COVENANTS AND AGREEMENTS.

     8.1. COOPERATION WITH THE CONSTRUCTION AGENT OR THE LESSEE.

     The Holders, the Lenders, the Lessor (at the direction of the Majority
Secured Parties) and the Agent shall, at the expense of and to the extent
reasonably requested by the Construction Agent or the Lessee (but without
assuming additional liabilities on account thereof and only to the extent such
additional liabilities are acceptable to the Agent in its reasonable judgment),
cooperate with the Construction Agent or the Lessee in connection with the
Construction Agent or the Lessee satisfying its covenant obligations contained
in the Operative Agreements including without limitation at any time and from
time to time, promptly and duly executing and delivering any and all such
further instruments, documents and financing statements (and continuation
statements related thereto) as the Construction Agent or the Lessee may
reasonably request.

     8.2. COVENANTS OF THE OWNER TRUSTEE AND THE HOLDERS.

     Each of the Owner Trustee and the Holders hereby agrees that so long as
this Agreement is in effect:

          (a) Neither the Owner Trustee (in its trust capacity or in its
     individual capacity) nor any Holder will create or permit to exist at any
     time, and each of them will, at its own cost and expense, promptly take
     such action as may be necessary duly to discharge, or to cause to be
     discharged, all Lessor Liens on the Properties attributable to it;
     provided, however, that the Owner Trustee and the Holders shall not be
     required to so 

                                       26
<PAGE>
 
     discharge any such Lessor Lien while the same is being contested in good
     faith by appropriate proceedings diligently prosecuted so long as such
     proceedings shall not involve any material danger of impairment of the
     Liens of the Security Documents or involve any danger of the sale,
     forfeiture or loss of, and shall not interfere with the use or disposition
     of, any material part of any Property or title thereto or any interest
     therein or the payment of Rent;

          (b) Without prejudice to any right under the Trust Agreement of the
     Owner Trustee to resign (subject to requirement set forth in the Trust
     Agreement that such resignation shall not be effective until a successor
     shall have agreed to accept such appointment), or the Holders' rights under
     the Trust Agreement to remove the institution acting as the Owner Trustee
     (after consent to such removal by the Agent as provided in the Trust
     Agreement and by the Lessee as provided in the succeeding paragraph (c)
     below), each of the Owner Trustee and the Holders hereby agrees with the
     Lessee, the Construction Agent and the Agent (i) not to terminate or revoke
     the trust created by the Trust Agreement except as permitted by Article
     VIII of the Trust Agreement, (ii) not to amend, supplement, terminate or
     revoke or otherwise modify any provision of the Trust Agreement in such a
     manner as to adversely affect the rights of any such party without the
     prior written consent of such party and (iii) to comply with all of the
     terms of the Trust Agreement, the nonperformance of which would adversely
     affect any such party;

          (c) The Owner Trustee or any successor may resign or be removed by the
     Holders as the Owner Trustee, a successor Owner Trustee may be appointed
     and a corporation may become the Owner Trustee under the Trust Agreement,
     only in accordance with the provisions of Article IX of the Trust Agreement
     and, with respect to such appointment, with the consent of the Lessee,
     which consent shall not be unreasonably withheld or delayed;

          (d) The Owner Trustee, in its capacity as the Owner Trustee under the
     Trust Agreement, and not in its individual capacity, shall not contract
     for, create, incur or assume any Indebtedness, or enter into any business
     or other activity or enter into any contracts or agreements, other than
     pursuant to or under (i) documents executed prior to the Initial Closing
     Date with respect to the Bridge Financing or (ii) the Operative Agreements;

          (e) The Holders will not instruct the Owner Trustee to take any action
     in violation of the terms of any Operative Agreement;

          (f) Neither any Holder nor the Owner Trustee shall (i) commence any
     case, proceeding or other action with respect to the Owner Trustee under
     any existing or future law of any jurisdiction, domestic or foreign,
     relating to bankruptcy, insolvency, reorganization, arrangement, winding-
     up, liquidation, dissolution, composition or other relief with respect to
     it or its debts, or (ii) seek appointment of a receiver, trustee, custodian
     or other similar official with respect to the Owner Trustee or for all or
     any substantial benefit of the creditors of the Owner Trustee; and neither
     any Holder nor the 

                                       27
<PAGE>
 
     Owner Trustee shall take any action in furtherance of, or indicating its
     consent to, approval of, or acquiescence in, any of the acts set forth in
     this paragraph;

          (g) The Owner Trustee shall give prompt notice to the Lessee, the
     Holders and the Agent if the Owner Trustee's principal place of business or
     chief executive office, or the office where the records concerning the
     accounts or contract rights relating to any Property are kept, shall cease
     to be located at 79 South Main Street, Salt Lake City, Utah 84111, or if it
     shall change its name; and

          (h) The Owner Trustee shall take or refrain from taking such actions
     and grant or refrain from granting such approvals with respect to the
     Operative Agreements and/or relating to any Property in each case as
     directed in writing by the Agent (until such time as the Loans are paid in
     full, and then by the Majority Holders) or, in connection with Sections 8.5
     and 9.2 hereof, the Lessee; provided, however, that notwithstanding the
     foregoing provisions of this subparagraph (h) the Owner Trustee, the Agent,
     the Lenders and the Holders each acknowledge, covenant and agree that
     neither the Owner Trustee nor the Agent shall act or refrain from acting,
     regarding each Unanimous Vote Matter, until such party has received the
     approval of each Lender and each Holder affected by such matter.

     8.3.  CREDIT PARTY COVENANTS, CONSENT AND ACKNOWLEDGMENT.

          (a) Each Credit Party acknowledges and agrees that the Owner Trustee,
     pursuant to the terms and conditions of the Security Agreement and the
     Mortgage Instruments, shall create Liens respecting the various personal
     property, fixtures and real property described therein in favor of the
     Agent.  Each Credit Party hereby irrevocably consents to the creation,
     perfection and maintenance of such Liens.  Each Credit Party shall, to the
     extent reasonably requested by any of the other parties hereto, cooperate
     with the other parties to satisfy their covenants herein or in the other
     Operative Agreements, including without limitation at any time and from
     time to time promptly and duly executing and delivering any and all such
     future instruments, documents and financing statements (and continuation
     statements related thereto) as any other party hereto may reasonably
     request.

          (b) The Lessor hereby instructs each Credit Party, and each Credit
     Party hereby acknowledges and agrees, that until such time as the Loans and
     the Holder Advances are paid in full and the Liens evidenced by the
     Security Agreement and the Mortgage Instruments have been released (i) any
     and all Rent (excluding Excepted Payments which shall be payable to each
     Holder or other Person as appropriate) and any and all other amounts of any
     kind or type under any of the Operative Agreements due and owing or payable
     to any Person shall instead be paid directly to the Agent (excluding
     Excepted Payments which shall be payable to each Holder or other Person as
     appropriate) or as the Agent may direct from time to time for allocation
     and distribution in accordance with the procedures set forth in Section 8.7
     hereof, (ii) all rights of the Lessor under the Lease shall be exercised by
     the Agent and (iii) each Credit Party shall cause all notices,

                                       28
<PAGE>
 
     certificates, financial statements, communications and other information
     which are delivered, or are required to be delivered, to the Lessor, also
     to be delivered at the same time to the Agent.

          (c) No Credit Party shall consent to or permit any amendment,
     supplement or other modification of the terms or provisions of any
     Operative Agreement except in accordance with Section 12.4 of this
     Agreement.

          (d) The Lessee hereby covenants and agrees to cause an Appraisal or
     reappraisal (in form and substance satisfactory to the Agent and from an
     appraiser selected by the Agent) to be issued respecting any Property as
     requested by the Agent (i) at each and every time as such shall be required
     to satisfy any regulatory requirements imposed on the Agent, the Lessor,
     the Trust Company, any Lender and/or any Holder and (ii) from time to time
     after the occurrence and during the continuance of an Event of Default.

          (e) Each Credit Party hereby covenants and agrees that, except for
     amounts payable as Basic Rent, any and all payment obligations owing from
     time to time under the Operative Agreements by any Person to the Agent, any
     Lender, any Holder or any other Person shall (without further action) be
     deemed to be Supplemental Rent obligations payable by the Lessee.  Without
     limitation, such obligations shall include without limitation arrangement
     fees, administrative fees, participation fees, facility fees, unused fees,
     prepayment penalties, breakage costs, indemnities, trustee fees and
     transaction expenses incurred by the parties hereto in connection with the
     transactions contemplated by the Operative Agreements.

          (f) At any time the Lessor or the Agent is entitled under the
     Operative Agreements to possession of a Property or any component thereof,
     each of the Construction Agent and the Lessee hereby covenants and agrees,
     at its own cost and expense, to assemble (in the case of tangible personal
     property) and make the same available to the Agent (on behalf of the
     Lessor).

          (g) The Lessee hereby covenants and agrees that respecting all
     Properties in the aggregate subject to the Lease at any time (and without
     respect to analysis on a Property by Property basis), (i) Non-Integral
     Equipment financed under the Operative Agreements may constitute up to, but
     not to exceed, fifteen percent (15%) of the aggregate Advances extended at
     or prior to such time and (ii) Equipment (including without limitation such
     Non-Integral Equipment) financed under the Operative Agreements may
     constitute up to, but not to exceed fifty percent (50%) of the aggregate
     Advances extended at or prior to such time.

          (h) The Lessee hereby covenants and agrees that as of Completion (i)
     the Property Cost for each individual parcel of the Property shall be no
     less than $2,000,000 and (ii) each parcel of the Property shall be a
     Permitted Facility.

                                       29
<PAGE>
 
          (i) The Lessee hereby covenants and agrees that it shall give prompt
     notice to the Agent if the Lessee's principal place of business or chief
     executive office, or the office where the records concerning the accounts
     or contract rights relating to any Property are kept, shall cease to be
     located at Houston, Harris County, Texas or if it shall change its name.

          (j) The Lessee hereby covenants and agrees that the aggregate Property
     Cost of Properties purchased for any reason by the Lessee pursuant to its
     Purchase Option prior to the Expiration Date shall not exceed ten percent
     (10%) of the aggregate Property Cost for all Properties funded during the
     Commitment Period.

          (k) The Lessee hereby covenants and agrees that the rights of the
     Lessee under this Agreement and the Lease shall not impair or in any way
     diminish the obligations of the Construction Agent and/or the rights of the
     Lessor under the Agency Agreement.

          (l) Within forty-five (45) days after the end of each of the first
     three fiscal quarters of each fiscal year of the Lessee (beginning with the
     fiscal quarter ending March 31, 1998) and within one-hundred (100) days
     after the close of each fiscal year of the Lessee (beginning with the
     fiscal year ending December 31, 1997), the Lessee hereby covenants and
     agrees to deliver to the Agent, the Lenders and the Holders a Compliance
     Certificate and a Covenant Compliance Worksheet reflecting the computation
     of the financial covenants incorporated by reference into the Lease
     pursuant to Section 28.1 of the Lease as of the last day of the period
     covered by such financial statements.

          (m) Each Credit Party agrees that the Tranche A Loans, the Tranche B
     Loans and the Certificates will be treated as debt of AOR for purposes of
     calculating financial covenants.

          (n) Each Credit Party shall promptly notify the Agent, or cause the
     Agent to be promptly notified, upon such Credit Party gaining knowledge of
     the occurrence of any Default or Event of Default which is continuing at
     such time.  In any event, such notice shall be provided to the Agent within
     ten (10) days of when an officer of such Credit Party gains such knowledge.

          (o) Until all of the obligations under the Operative Agreements have
     been finally and indefeasibly paid and satisfied in full and the
     Commitments and the Holder Commitments terminated unless consent has been
     obtained from the Majority Secured Parties, each Credit Party will:

               (i) except as permitted by the express provisions of the Lessee
          Credit Agreement, preserve and maintain its separate legal existence
          and all rights, franchises, licenses and privileges necessary to the
          conduct of its business, and qualify and remain qualified as a foreign
          corporation (or partnership, limited liability company or other such
          similar entity, as the case may be) and authorized 

                                       30
<PAGE>
 
          to do business in each jurisdiction in which the failure to do so
          qualify shall have or could reasonably be expected to have a Material
          Adverse Effect;

               (ii) pay and perform all obligations of the Credit Parties under
          the Operative Agreements and pay or perform (A) all taxes, assessments
          and other governmental charges that may be levied or assessed upon it
          or any of its property, and (B) all other indebtedness, obligations
          and liabilities in accordance with customary trade practices, which in
          the case of each of (A) and (B) if not paid shall have or could
          reasonably be expected to have a Material Adverse Effect; provided,
          that any Credit Party may contest any item described in this Section
          8.3(o)(ii) in good faith so long as adequate reserves are maintained
          with respect thereto in accordance with GAAP;

               (iii)  do each of the following to the extent failure to do so
          shall have or could reasonably be expected to have a Material Adverse
          Effect: observe and remain in compliance with all applicable Laws and
          maintain in full force and effect all Governmental Actions, in each
          case applicable to the conduct of its business; keep or cause to be
          kept in full force and effect all licenses, certifications or
          accreditations necessary for any Permitted Facility to carry on its
          business; and

               (iv)  provided, that the Agent, the Lenders and the Holders use
          reasonable efforts to minimize disruption to the business of the
          Credit Parties, permit representatives of the Agent or any Lender or
          any Holder, from time to time upon reasonable notice and during normal
          banking hours to do each of the following: to visit and inspect its
          properties; inspect, audit and make extracts from its books, records
          and files, including without limitation management letters prepared by
          independent accountants; and discuss with its principal officers, and
          (in the presence of its officers) its independent accountants, its
          business, assets, liabilities, financial condition, results of
          operations and business prospects.

     8.4. SHARING OF CERTAIN PAYMENTS.

     Except for Excepted Payments, the parties hereto acknowledge and agree that
all payments due and owing by any Credit Party to the Lessor under the Lease or
any of the other Operative Agreements shall be made by such Credit Party
directly to the Agent as more particularly provided in Section 8.3 hereof. The
Lessor, the Holders, the Agent, the Lenders and the Credit Parties acknowledge
the terms of Section 8.7 of this Agreement regarding the allocation of payments
and other amounts made or received from time to time under the Operative
Agreements and agree, that all such payments and amounts are to be allocated as
provided in Section 8.7 of this Agreement.

                                       31
<PAGE>
 
     8.5. GRANT OF EASEMENTS, ETC.

     The Agent, the Lenders and the Holders hereby agree that, so long as no
Event of Default shall have occurred and be continuing, the Owner Trustee shall,
from time to time at the request of the Lessee (and with the prior consent of
the Agent), in connection with the transactions contemplated by the Agency
Agreement, the Lease or the other Operative Agreements, (i) grant easements and
other rights in the nature of easements with respect to any Property, (ii)
release existing easements or other rights in the nature of easements which are
for the benefit of any Property, (iii) execute and deliver to any Person any
instrument appropriate to confirm or effect such grants or releases, and (iv)
execute and deliver to any Person such other documents or materials in
connection with the acquisition, development, construction, testing or operation
of any Property, including without limitation reciprocal easement agreements,
construction contracts, operating agreements, development agreements, plats,
replats or subdivision documents; provided, that each of the agreements referred
to in this Section 8.5 shall be of the type normally executed by the Lessee or
its Affiliates or other Persons operating businesses similar to the businesses
of Lessee and/or its Affiliates and similarly situated to Lessee and/or its
Affiliates in the ordinary course of such firm's business and shall be on
commercially reasonable terms so as not to diminish the value of any Property in
any material respect.

     8.6. APPOINTMENT OF THE AGENT BY THE LENDERS, THE HOLDERS AND THE OWNER
          TRUSTEE.

     The Holders hereby appoint the Agent to act as collateral agent for the
Holders in connection with the Lien granted by the Security Documents to secure
the Holder Amount. The Lenders and the Holders acknowledge and agree and direct
that the rights and remedies of the beneficiaries of the Lien of the Security
Documents shall be exercised by the Agent on behalf of the Lenders and the
Holders as directed from time to time by the Majority Secured Parties or,
pursuant to Sections 8.2(h) and 12.4, all of the Lenders and the Holders, as the
case may be; provided, in all cases, the Agent shall allocate payments and other
amounts received in accordance with Section 8.7; provided, further, the Agent
shall take directions with respect to the guaranty provisions of (a) Sections
8B.1 through 8B.8 of the Credit Agreement from the Tranche A Lenders holding
sixty-six and two thirds percent (66 2/3%), of the aggregate Tranche A Loans
outstanding and (b) Sections 8C.1 through 8C.8 of the Credit Agreement from the
Majority Secured Parties. The Agent is further appointed to provide notices
under the Operative Agreements on behalf of the Owner Trustee (as determined by
the Agent, in its reasonable discretion), to receive notices under the Operative
Agreements on behalf of the Owner Trustee and (subject to Sections 8.5 and 9.2)
to take such other action which the Owner Trustee is entitled to take under the
Operative Agreements on behalf of the Owner Trustee as the Agent shall determine
in its reasonable discretion from time to time. The Agent hereby accepts such
appointments. For purposes hereof, the provisions of Section 7 of the Credit
Agreement, together with such other terms and provisions of the Credit Agreement
and the other Operative Agreements as required for the full interpretation and
operation of Section 7 of the Credit Agreement are hereby incorporated by
reference as if restated herein for the mutual benefit of the Agent and each
Holder as if each Holder were a Lender thereunder. Outstanding Holder Advances
and outstanding Loans shall each be taken into account for purposes of
determining 

                                       32
<PAGE>
 
Majority Secured Parties. Further, the Agent shall be entitled to take such
action on behalf of the Owner Trustee as is delegated to the Agent under any
Operative Agreement (whether express or implied) as may be reasonably incidental
thereto. The parties hereto hereby agree to the provisions contained in this
Section 8.6. Any appointment of a successor agent under Section 7.9 of the
Credit Agreement shall also be effective as an appointment of a successor agent
for purposes of this Section 8.6.

     8.6B.  APPOINTMENT OF THE LESSOR BY THE LENDERS AND THE HOLDERS.

     The Lenders and the Holders hereby appoint the Lessor to act as collateral
agent for the Lenders and the Holders in connection with the Lien granted by the
Lease to secure the obligations of each Credit Party under any and all Operative
Agreements. The Lessor accepts such appointment. The Lessor hereby agrees, and
the Lenders and the Holders hereby acknowledge, that (to the extent not
otherwise set forth in any other Operative Agreement) all right, title and
interest of the Lessor in, to and under the Lease is hereby further assigned to
the Agent, for the benefit of the Lenders and the Holders, as collateral to
secure the obligations of the Lessor and each Credit Party under any and all
Operative Agreements.

     8.7. COLLECTION AND ALLOCATION OF PAYMENTS AND OTHER AMOUNTS.

          (a) Each Credit Party has agreed pursuant to the terms of this
     Agreement to pay to (i) the Agent any and all Rent (excluding Excepted
     Payments) and any and all other amounts of any kind or type under any of
     the Operative Agreements due and owing or payable to any Person and (ii)
     each Person as appropriate the Excepted Payments.  Promptly after receipt,
     the Agent shall apply and allocate, in accordance with the terms of this
     Section 8.7, such amounts received from any Credit Party and all other
     payments, receipts and other consideration of any kind whatsoever received
     by the Agent pursuant to the Security Agreement or otherwise received by
     the Agent, the Holders or any of the Lenders in connection with the
     Collateral, the Security Documents or any of the other Operative
     Agreements.  Ratable distributions among the Lenders and the Holders under
     this Section 8.7 shall be made based on (in the case of the Lenders) the
     ratio of the outstanding Loans to the aggregate Property Cost and (in the
     case of the Holders) the ratio of the outstanding Holder Advances to the
     aggregate Property Cost.  Ratable distributions among the Tranche A Lenders
     under this Section 8.7 shall be made based on the ratio of the individual
     Tranche A Lender's Commitment for Tranche A Loans to the aggregate of all
     the Tranche A Lenders' Commitments for Tranche A Loans. Ratable
     distributions among the Tranche B Lenders under this Section 8.7 shall be
     made based on the ratio of the individual Tranche B Lender's Commitment for
     Tranche B Loans to the aggregate of all the Tranche B Lenders' Commitments
     for Tranche B Loans. Ratable distributions among the Lenders (in situations
     where the Tranche A Lenders are not differentiated from the Tranche B
     Lenders) shall be made based on the ratio of the individual Lender's
     Commitment to the aggregate of all the Lenders' Commitments. Ratable
     distributions among the Holders under this Section 8.7 shall be based on
     the ratio of the individual Holder's Holder Commitment to the aggregate of
     all the Holders' Holder Commitments.

                                       33
<PAGE>
 
          (b) Payments and other amounts received by the Agent from time to time
     in accordance with the terms of subparagraph (a) shall be applied and
     allocated as follows:

               (i)   Any such payment or amount identified as or deemed to be
          Basic Rent shall be applied and allocated by the Agent first, ratably
          to the Lenders and the Holders for application and allocation to the
          payment of interest on the Loans and thereafter the principal of the
          Loans which is due and payable on such date and to the payment of
          accrued Holder Yield with respect to the Holder Advances and
          thereafter the portion of the Holder Advances which is due on such
          date; and second, if no Default or Event of Default is in effect, any
          excess shall be paid to such Person or Persons as the Lessee may
          designate; provided, that if a Default or Event of Default is in
          effect, such excess (if any) shall instead be held by the Agent until
          the earlier of (I) the first date thereafter on which no Default or
          Event of Default shall be in effect (in which case such payments or
          returns shall then be made to such other Person or Persons as the
          Lessee may designate) and (II) the Maturity Date or the Expiration
          Date, as the case may be (or, if earlier, the date of any
          Acceleration), in which case such amounts shall be applied and
          allocated in the manner contemplated by Section 8.7(b)(iv).

               (ii)  If on any date the Agent or the Lessor shall receive any
          amount in respect of (A) any Casualty or Condemnation pursuant to
          Sections 15.1(a) or 15.1(g) of the Lease (excluding any payments in
          respect thereof which are payable to the Lessee in accordance with the
          Lease), or (B) the Termination Value in connection with the delivery
          of a Termination Notice pursuant to Article XVI of the Lease, or (C)
          the Termination Value in connection with the exercise of the Purchase
          Option under Section 20.1 of the Lease or the exercise of the option
          of the Lessor to transfer the Properties to the Lessee pursuant to
          Section 20.3 of the Lease, or (D) any payment required to be made or
          elected to be made by the Construction Agent to the Lessor pursuant to
          the terms of the Agency Agreement, then in each case, the Lessor shall
          be required to pay such amount received (1) if no Acceleration has
          occurred, to prepay the principal balance of the Loans and the Holder
          Advances, on a pro rata basis, a portion of such amount to be
          distributed to the Lenders and the Holders or (2) if an Acceleration
          has occurred, to apply and allocate the proceeds respecting Sections
          8.7(b)(ii)(A) through 8.7(b)(ii)(D) in accordance with Section
          8.7(b)(iii) hereof.

               (iii) Subject to Section 8.7(c), an amount equal to any payment
          identified as proceeds of the sale or other disposition (or lease upon
          the exercise of remedies) of the Properties or any portion thereof,
          whether pursuant to Article XXII of the Lease or the exercise of
          remedies under the Security Documents or otherwise, the execution of
          remedies set forth in the Lease and any payment in respect of excess
          wear and tear pursuant to Section 22.3 of the Lease (whether such
          payment relates to a period before or after the Construction Period
          Termination Date) shall be applied and allocated by the Agent first,
          ratably to the 

                                       34
<PAGE>
 
          payment of the principal and interest of the Tranche B Loans then
          outstanding, second, ratably to the payment to the Holders of the
          outstanding principal balance of all Holder Advances plus all
          outstanding Holder Yield with respect to such outstanding Holder
          Advances, third, to the extent such amount exceeds the maximum amount
          to be returned pursuant to the foregoing provisions of this paragraph
          (iii), ratably to the payment of the principal and interest of the
          Tranche A Loans then outstanding, fourth, to any and all other amounts
          owing under the Operative Agreements to the Lenders under the Tranche
          B Loans, fifth, to any and all other amounts owing under the Operative
          Agreements to the Holders, sixth, to any and all other amounts owing
          under the Operative Agreements to the Lenders under the Tranche A
          Loans, and seventh, to the extent moneys remain after application and
          allocation pursuant to clauses first through sixth above, to the Owner
          Trustee for application and allocation to any and all other amounts
          owing to the Holders or the Owner Trustee and as the Holders shall
          determine; provided, where no Event of Default shall exist and be
          continuing and a prepayment is made for any reason with respect to
          less than the full amount of the outstanding principal amount of the
          Loans and the outstanding Holder Advances, the proceeds shall be
          applied and allocated ratably to the Lenders and to the Holders.

               (iv)  Subject to Section 8.7(c), an amount equal to (A) any such
          payment identified as a payment pursuant to Section 22.1(b) of the
          Lease (or otherwise) of the Maximum Residual Guarantee Amount (and any
          such lesser amount as may be required by Section 22.1(b) of the Lease)
          in respect of the Properties, (B) any other amount payable upon any
          exercise of remedies after the occurrence of an Event of Default not
          covered by Sections 8.7(b)(i) or 8.7(b)(iii) above (including without
          limitation any amount received in connection with an Acceleration
          which does not represent proceeds from the sale or liquidation of the
          Properties), (C) any amount paid by the Tranche A Guarantors pursuant
          to Sections 8B.1 - 8B.8 of the Credit Agreement and/or by the
          Guarantor pursuant to Sections 8C.1 - 8C.8 of the Credit Agreement and
          (D) any amount received with respect to the collateral which secures
          both the Lessee Credit Agreement and any obligations under the
          Operative Agreements, shall be applied and allocated by the Agent
          first, ratably, to the payment of the principal and interest balance
          of Tranche A Loans then outstanding, second, ratably to the payment of
          the principal and interest balance of the Tranche B Loans then
          outstanding, third, ratably to the payment of the principal balance of
          all Holder Advances plus all outstanding Holder Yield with respect to
          such outstanding Holder Advances, fourth, to the payment of any other
          amounts owing to the Lenders hereunder or under any of the other
          Operative Agreement, and fifth, to the extent moneys remain after
          application and allocation pursuant to clauses first through fourth
          above, to the Owner Trustee for application and allocation to Holder
          Advances and Holder Yield and any other amounts owing to the Holders
          or the Owner Trustee as the Holders shall determine.

                                       35
<PAGE>
 
               (v)   An amount equal to any such payment identified as
          Supplemental Rent shall be applied and allocated by the Agent to the
          payment of any amounts then owing to the Agent, the Lenders, the
          Holders and the other parties to the Operative Agreements (or any of
          them) (other than any such amounts payable pursuant to the preceding
          provisions of this Section 8.7(b)) as shall be determined by the Agent
          in its reasonable discretion; provided, however, that Supplemental
          Rent received upon the exercise of remedies after the occurrence and
          continuance of an Event of Default in lieu of or in substitution of
          the Maximum Residual Guarantee Amount or as a partial payment thereon
          shall be applied and allocated as set forth in Section 8.7(b)(iv).

               (vi) The Agent in its reasonable judgment shall identify the
          nature of each payment or amount received by the Agent and apply and
          allocate each such amount in the manner specified above.

          (c) Upon the termination of the Commitments and the Holder Commitments
     and the indefeasible payment in full of all Loans, all Holder Advances and
     all other amounts owing by the Owner Trustee or any Credit Party in
     accordance with any Operative Agreement, any excess moneys remaining with
     the Agent with regard to one or more of the Properties shall be returned to
     the Lessee.  In the event of an Acceleration it is agreed that, prior to
     the application and allocation of amounts received by the Agent in the
     order described in Section 8.7(b) above, any such amounts shall first be
     applied and allocated to the payment of (i) any and all sums advanced by
     the Agent in order to preserve the Collateral or to preserve its Lien
     thereon, (ii) the expenses of retaking, holding, preparing for sale or
     lease, selling or otherwise disposing or realizing on the Collateral, or of
     any exercise by the Agent of its rights under the Security Documents,
     together with reasonable attorneys' fees and expenses and court costs and
     (iii) any and all other amounts reasonably owed to the Agent in accordance
     with the transactions contemplated by the Operative Agreements (including
     without limitation any accrued and unpaid administration fees).

     8.8. RELEASE OF PROPERTIES, ETC.

     If the Lessee shall at any time purchase any Property pursuant to the
Lease, or the Construction Agent shall purchase any Property pursuant to the
Agency Agreement, or if any Property shall be sold in accordance with Article
XXII of the Lease, then, upon satisfaction by the Owner Trustee of its
obligation to prepay the Loans, Holder Advances and all other amounts owing to
the Lenders and the Holders under the Operative Agreements, the Agent is hereby
authorized and directed to release such Properties from the Liens created by the
Security Documents to the extent of its interest therein. In addition, upon the
termination of the Commitments and the Holder Commitments and the payment in
full of the Loans, the Holder Advances and all other amounts owing by the Owner
Trustee hereunder or under any other Operative Agreement, the Agent is hereby
authorized and directed to release all of the Properties from the Liens created
by the Security Documents to the extent of its interest therein. Upon request of
the Owner Trustee or the Lessee following any such release, the Agent shall, at
the

                                       36
<PAGE>
 
sole cost and expense of the Lessee, execute and deliver to the Owner Trustee
and the Lessee such documents as the Owner Trustee or the Lessee shall
reasonably request to evidence such release.


               SECTION 9.  CREDIT AGREEMENT AND TRUST AGREEMENT.

     9.1. THE CONSTRUCTION AGENT'S AND THE LESSEE'S CREDIT AGREEMENT RIGHTS.

     Notwithstanding anything to the contrary contained in the Credit Agreement,
the Agent, the Lenders, the Holders, the Credit Parties and the Owner Trustee
hereby agree that, prior to the occurrence and continuation of any Default
(except with respect to subsections (a), (b), (d) or (g) which shall apply in
the case of a Default) or Event of Default (except with respect to subsections
(a), (b), (d) or (g) which shall apply in the case of an Event of Default), the
Construction Agent or the Lessee, as the case may be, shall have the following
rights:

          (a) the right to designate an account to which amounts funded under
     the Operative Agreements shall be credited pursuant to Section 2.3(a) of
     the Credit Agreement;

          (b) the right to terminate or reduce the Commitments pursuant to
     Section 2.5(a) of the Credit Agreement;

          (c) the right to exercise the conversion and continuation options
     pursuant to Section 2.7 of the Credit Agreement;

          (d) the right to receive any notice and any certificate, in each case
     issued pursuant to Sections 2.9(c) and/or 2.11(a) of the Credit Agreement;

          (e) the right to replace any Lender pursuant to Section 2.11(b) of the
     Credit Agreement;

          (f) the right to approve any successor agent pursuant to Section 7.9
     of the Credit Agreement; and

          (g) the right to consent to any assignment by a Lender to which the
     Lessor has the right to consent pursuant to Section 9.8 of the Credit
     Agreement.

     9.2. THE CONSTRUCTION AGENT'S AND THE LESSEE'S TRUST AGREEMENT RIGHTS.

     Notwithstanding anything to the contrary contained in the Trust Agreement,
the Credit Parties, the Owner Trustee and the Holders hereby agree that, prior
to the occurrence and continuation of any Default (except with respect to
subsection (b) which shall apply in the case of a Default) or Event of Default
(except with respect to subsection (b) which shall apply in the 

                                       37
<PAGE>
 
case of an Event of Default), the Construction Agent or the Lessee, as the case
may be, shall have the following rights:

          (a) the right to exercise the conversion and continuation options
     pursuant to Section 3.8 of the Trust Agreement;

          (b) the right to receive any notice and any certificate, in each case
     issued pursuant to Section 3.9(a) of the Trust Agreement;

          (c) the right to replace any Holder pursuant to Section 3.9(b) of the
     Trust Agreement;

          (d) the right to exercise the removal options contained in Section 3.9
     of the Trust Agreement; and

          (e) no removal of the Owner Trustee and appointment of a successor
     Owner Trustee pursuant to Section 9.1 of the Trust Agreement shall be made
     without the prior written consent (not to be unreasonably withheld or
     delayed) of the Lessee.


SECTION 10.  TRANSFER OF INTEREST.

     10.1.  RESTRICTIONS ON TRANSFER.

     Each Lender may participate, assign or transfer all or a portion of its
interest hereunder and under the other Operative Agreements in accordance with
Sections 9.7 and 9.8 of the Credit Agreement; provided, at such time each
participant, assignee or transferee must obtain the same ratable interest in
Tranche A Loans, the Tranche B Loans and the Lessee Credit Agreement. The
Holders may, directly or indirectly, assign, convey or otherwise transfer any of
their right, title or interest in or to the Trust Estate or the Trust Agreement
with the prior written consent of the Agent and the Lessee (which consent shall
not be unreasonably withheld or delayed) and in accordance with the terms of
Section 11.8(b) of the Trust Agreement. The Owner Trustee may, subject to the
rights of the Lessee under the Lease and the other Operative Agreements and to
the Lien of the applicable Security Documents but only with the prior written
consent of the Agent (which consent may be withheld by the Agent in its sole
discretion) and (provided, no Default or Event of Default has occurred and is
continuing) with the consent of the Lessee, directly or indirectly, assign,
convey, appoint an agent with respect to enforcement of, or otherwise transfer
any of its right, title or interest in or to any Property, the Lease, the Trust
Agreement and the other Operative Agreements (including without limitation any
right to indemnification thereunder), or any other document relating to a
Property or any interest in a Property as provided in the Trust Agreement and
the Lease. The provisions of the immediately preceding sentence shall not apply
to the obligations of the Owner Trustee to transfer Property to the Lessee or a
third party purchaser pursuant to Article XXII of the Lease upon payment for
such Property in accordance with the terms and conditions of the Lease. No
Credit Party may assign any of the Operative Agreements or any of their
respective rights or obligations thereunder or with respect 

                                       38
<PAGE>
 
to any Property in whole or in part to any Person without the prior written
consent of the Agent, the Lenders, the Holders and the Lessor.

     10.2.  EFFECT OF TRANSFER.

     From and after any transfer effected in accordance with this Section 10,
the transferor shall be released, to the extent of such transfer, from its
liability hereunder and under the other documents to which it is a party in
respect of obligations to be performed on or after the date of such transfer;
provided, however, that any transferor shall remain liable hereunder and under
such other documents to the extent that the transferee shall not have assumed
the obligations of the transferor thereunder. Upon any transfer by the Owner
Trustee, a Holder or a Lender as above provided, any such transferee shall
assume the obligations of the Owner Trustee, the Holder or the Lender, as the
case may be, and shall be deemed an "Owner Trustee", "Holder", or "Lender", as
the case may be, for all purposes of such documents and each reference herein to
the transferor shall thereafter be deemed a reference to such transferee for all
purposes, except as provided in the preceding sentence. Notwithstanding any
transfer of all or a portion of the transferor's interest as provided in this
Section 10, the transferor shall be entitled to all benefits accrued and all
rights vested prior to such transfer including without limitation rights
theretofore accrued to indemnification under any such document.


                         SECTION 11.  INDEMNIFICATION.

     11.1.  GENERAL INDEMNITY.

     Whether or not any of the transactions contemplated hereby shall be
consummated, the Indemnity Provider hereby assumes liability for and agrees to
defend, indemnify and hold harmless each Indemnified Person on an After Tax
Basis from and against any Claims, which may be imposed on, incurred by or
asserted against an Indemnified Person by any third party, including without
limitation Claims arising from the negligence of an Indemnified Person (but not
to the extent such Claims arise from the gross negligence or willful misconduct
of such Indemnified Person itself, as determined by a court of competent
jurisdiction) in any way relating to or arising or alleged to arise out of the
execution, delivery, performance or enforcement of this Agreement, the Lease or
any other Operative Agreement or on or with respect to any Property or any
component thereof, including without limitation Claims in any way relating to or
arising or alleged to arise out of (a) the financing, refinancing, purchase,
acceptance, rejection, ownership, design, construction, refurbishment,
development, delivery, acceptance, nondelivery, leasing, subleasing, possession,
use, occupancy, operation, maintenance repair, modification, transportation,
condition, sale, return, repossession (whether by summary proceedings or
otherwise), or any other disposition of any Property or any part thereof,
including without limitation the acquisition, holding or disposition of any
interest in the Property, lease or agreement comprising a portion of any
thereof; (b) any latent or other defects in any Property or any portion thereof
whether or not discoverable by an Indemnified Person or the Indemnity Provider;
(c) a violation of Environmental Laws, Environmental Claims or other loss of or

                                       39
<PAGE>
 
damage to any property or the environment relating to the Property, the Lease,
the Agency Agreement or the Indemnity Provider; (d) the Operative Agreements, or
any transaction contemplated thereby; (e) any breach by the Indemnity Provider
of any of its representations or warranties under the Operative Agreements to
which the Indemnity Provider is a party or failure by the Indemnity Provider to
perform or observe any covenant or agreement to be performed by it under any of
the Operative Agreements; (f) the transactions contemplated hereby or by any
other Operative Agreement, in respect of the application of Parts 4 and 5 of
Subtitle B of Title I of ERISA; and (g) personal injury, death or property
damage, including without limitation Claims based on strict or absolute
liability in tort. All Claims relating to Impositions which otherwise would be
subject to this Section 11.1 shall instead be subject to the provisions of
Section 11.2.

     If a written Claim is made against any Indemnified Person or if any
proceeding shall be commenced against such Indemnified Person (including without
limitation a written notice of such proceeding), for any Claim, such Indemnified
Person shall promptly notify the Indemnity Provider in writing and shall not
take action with respect to such Claim without the consent of the Indemnity
Provider for thirty (30) days after the receipt of such notice by the Indemnity
Provider; provided, however, that in the case of any such Claim, if action shall
be required by law or regulation to be taken prior to the end of such period of
thirty (30) days, such Indemnified Person shall endeavor to, in such notice to
the Indemnity Provider, inform the Indemnity Provider of such shorter period,
and no action shall be taken with respect to such Claim without the consent of
the Indemnity Provider before seven (7) days before the end of such shorter
period; provided, further, that the failure of such Indemnified Person to give
the notices referred to in this sentence shall not diminish the Indemnity
Provider's obligation hereunder except to the extent such failure precludes the
Indemnity Provider from contesting such Claim and then only to the extent of
such actual preclusion.

     If, within thirty (30) days of receipt of such notice from the Indemnified
Person (or such shorter period as the Indemnified Person has notified the
Indemnity Provider is required by law or regulation for the Indemnified Person
to respond to such Claim), the Indemnity Provider shall request in writing that
such Indemnified Person respond to such Claim, the Indemnified Person shall, at
the expense of the Indemnity Provider, in good faith conduct and control such
action (including without limitation by pursuit of appeals) (provided, however,
that (A) at the Indemnity Provider's request, shall allow the Indemnity Provider
to conduct and control the response to such Claim and (B) in the case of any
Claim (and notwithstanding the provisions of the foregoing subsection (A)), the
Indemnified Person may request the Indemnity Provider to conduct and control the
response to such Claim (with counsel to be selected by the Indemnity Provider
and consented to by such Indemnified Person, such consent not to be unreasonably
withheld; provided, however, that any Indemnified Person may retain separate
counsel at the expense of the Indemnity Provider in the event of a conflict of
interest between such Indemnified Person and the Indemnity Provider)) by, in the
sole discretion of the Person conducting and controlling the response to such
Claim (1) resisting payment thereof, (2) not paying the same except under
protest, if protest is necessary and proper, (3) if the 

                                       40
<PAGE>
 
payment be made, using reasonable efforts to obtain a refund thereof in
appropriate administrative and judicial proceedings, or (4) taking such other
action as is reasonably requested by the Indemnity Provider from time to time.

     The party controlling the response to any Claim shall consult in good faith
with the non-controlling party and shall keep the non-controlling party
reasonably informed as to the conduct of the response to such Claim; provided,
that all decisions ultimately shall be made in the discretion of the controlling
party. The parties agree that an Indemnified Person may at any time decline to
take further action with respect to the response to such Claim and may settle
such Claim if such Indemnified Person shall waive its rights to any indemnity
from the Indemnity Provider that otherwise would be payable in respect of such
Claim (and any future Claim, the pursuit of which is precluded by reason of such
resolution of such Claim) and shall pay to the Indemnity Provider any amount
previously paid or advanced by the Indemnity Provider pursuant to this Section
11.1 by way of indemnification or advance for the payment of an amount regarding
such Claim.

     Notwithstanding the foregoing provisions of this Section 11.1, an
Indemnified Person shall not be required to take any action (except to consult
with the Indemnity Provider and to keep the Indemnity Provider reasonably
informed as set forth above unless such Indemnified Person determines in good
faith that there exists a conflict of interest between such Indemnified Person
and the Indemnity Provider) and no Indemnity Provider shall be permitted to
respond to any Claim in its own name or that of the Indemnified Person unless
(A) the Indemnity Provider shall have agreed to pay and shall pay to such
Indemnified Person on demand and on an After Tax Basis all reasonable costs,
losses and expenses that such Indemnified Person actually incurs in connection
with such Claim, including without limitation all reasonable legal, accounting
and investigatory fees and disbursements and, if the Indemnified Person has
informed the Indemnity Provider that it intends to contest such Claim (whether
or not the control of the contest is then assumed by the Indemnity Provider),
the Indemnity Provider shall have agreed that the Claim is an indemnifiable
Claim hereunder, (B) in the case of a Claim that must be pursued in the name of
an Indemnified Person (or an Affiliate thereof), the amount of the potential
indemnity (taking into account all similar or logically related Claims that have
been or could be raised for which the Indemnity Provider may be liable to pay an
indemnity under this Section 11.1) exceeds $25,000 (or such lesser amount as may
be subsequently agreed between the Indemnity Provider and the Indemnified
Person), (C) the Indemnified Person shall have reasonably determined that the
action to be taken will not result in any material danger of sale, forfeiture or
loss of the Property, or any part thereof or interest therein, will not
interfere with the payment of Rent, and will not result in risk of criminal
liability, (D) if such Claim shall involve the payment of any amount prior to
the resolution of such Claim, the Indemnity Provider shall provide to the
Indemnified Person an interest-free advance in an amount equal to the amount
that the Indemnified Person is required to pay (with no additional net after-tax
cost to such Indemnified Person) prior to the date such payment is due, (E) in
the case of a Claim that must be pursued in the name of an Indemnified Person
(or an Affiliate thereof), the Indemnity Provider shall have provided to such
Indemnified Person an opinion of independent counsel selected by the Indemnity
Provider and 

                                       41
<PAGE>
 
reasonably satisfactory to the Indemnified Person stating that a reasonable
basis exists to contest such Claim (or, in the case of an appeal of an adverse
determination, an opinion of such counsel to the effect that the position
asserted in such appeal will more likely than not prevail) and (F) no Event of
Default shall have occurred and be continuing. In no event shall an Indemnified
Person be required to appeal an adverse judicial determination to the United
States Supreme Court. In addition, an Indemnified Person shall not be required
to contest any Claim in its name (or that of an Affiliate) if the subject matter
thereof shall be of a continuing nature and shall have previously been decided
adversely by a court of competent jurisdiction pursuant to the contest
provisions of this Section 11.1, unless there shall have been a change in law
(or interpretation thereof) and the Indemnified Person shall have received, at
the Indemnity Provider's expense, an opinion of independent counsel selected by
the Indemnity Provider and reasonably acceptable to the Indemnified Person
stating that as a result of such change in law (or interpretation thereof), it
is more likely than not that the Indemnified Person will prevail in such
contest. In no event shall the Indemnity Provider be permitted to negotiate or
settle any Claim without the consent of the Indemnified Person to the extent any
loss, adjustment or settlement involves, or is reasonably likely to involve, any
performance by or adverse admission by or with respect to the Indemnified
Person.


     11.2.  GENERAL TAX INDEMNITY.

          (a) Subject to the following paragraph (b), the Indemnity Provider
     shall pay and assume liability for, and does hereby agree to indemnify,
     protect and defend each Property and all Indemnified Persons, and hold them
     harmless against, all Impositions on an After Tax Basis, and all payments
     pursuant to the Operative Agreements shall be made free and clear of and
     without deduction for any and all present and future Impositions.

          (b) Notwithstanding anything to the contrary in Section 11.2(a)
     hereof, the following shall be excluded from the indemnity required by
     Section 11.2(a):

               (i) Taxes (other than Taxes that are, or are in the nature
          of, sales, use, rental, value added, transfer or property taxes) that
          are imposed on a Indemnified Person (other than the Lessor, the Owner
          Trustee and the Trust except to the extent of fees and compensation
          paid to the Trust Company for acting as Owner Trustee under the
          Operative Agreements) by the United States federal government that are
          based on or measured by the net income or capital (including without
          limitation taxes based on capital gains and minimum taxes) of such
          Person; provided, that this clause (i) shall not be interpreted to
          prevent a payment from being made on an After Tax Basis if such
          payment is otherwise required to be so made;

               (ii) Taxes (other than Taxes that are, or are in the nature
          of, sales, use, rental, value added, transfer or property taxes) that
          are imposed on any 

                                       42
<PAGE>
 
          Indemnified Person (other than the Lessor, the Owner Trustee and the
          Trust except to the extent of fees and compensation paid to the Trust
          Company for acting as Owner Trustee under the Operative Agreements) by
          any state or local jurisdiction or taxing authority within any state
          or local jurisdiction and that are based upon or measured by the net
          income or capital (including without limitation taxes based on capital
          gains and minimum taxes) of such Person; provided, that this clause
          (ii) shall not be interpreted to prevent a payment from being made on
          an After Tax Basis if such payment is otherwise required to be so
          made;

               (iii)  any Tax to the extent it relates to any act, event or
          omission that occurs after the termination of the Lease and redelivery
          or sale of the Property in accordance with the terms of the Lease (but
          not any Tax that relates to such termination, redelivery or sale
          and/or to any period prior to such termination, redelivery or sale);
          and

               (iv) any Taxes which are imposed on an Indemnified Person as
          a result of the gross negligence or willful misconduct of such
          Indemnified Person itself, as determined by a court of competent
          jurisdiction, but not Taxes imposed as a result of ordinary negligence
          of such Indemnified Person;

          (c)  (i)  Subject to the terms of Section 11.2(f), the Indemnity
          Provider shall pay or cause to be paid all Impositions required to be
          paid under or pursuant to Section 11.2(a) directly to the taxing
          authorities where feasible and otherwise to the Indemnified Person, as
          appropriate, and the Indemnity Provider shall at its own expense, upon
          such Indemnified Person's reasonable request, furnish to such
          Indemnified Person copies of official receipts or other satisfactory
          proof evidencing such payment.

               (ii) In the case of Impositions for which no contest is conducted
          pursuant to Section 11.2(f) and which the Indemnity Provider pays
          directly to the taxing authorities, the Indemnity Provider shall pay
          such Impositions prior to the latest time permitted by the relevant
          taxing authority for timely payment. In the case of Impositions for
          which the Indemnity Provider reimburses an Indemnified Person, the
          Indemnity Provider shall do so within thirty (30) days after receipt
          by the Indemnity Provider of demand by such Indemnified Person
          describing in reasonable detail the nature of the Imposition and the
          basis for the demand (including without limitation the computation of
          the amount payable), accompanied by receipts or other reasonable
          evidence of such demand. In the case of Impositions for which a
          contest is conducted pursuant to Section 11.2(f), the Indemnity
          Provider shall pay such Impositions or reimburse such Indemnified
          Person for such Impositions, to the extent not previously paid or
          reimbursed pursuant to subsection (a), prior to the latest time
          permitted by the relevant taxing 

                                       43
<PAGE>
 
          authority for timely payment after conclusion of all contests under
          Section 11.2(f).

               (iii)  At the Indemnity Provider's request, the amount of any
          indemnification payment by the Indemnity Provider pursuant to
          subsection (a) shall be verified and certified by an independent
          public accounting firm mutually acceptable to the Indemnity Provider
          and the Indemnified Person. The fees and expenses of such independent
          public accounting firm shall be paid by the Indemnity Provider unless
          such verification shall result in an adjustment in the Indemnity
          Provider's favor of fifteen percent (15%) or more of the payment as
          computed by the Indemnified Person, in which case such fee shall be
          paid by the Indemnified Person.

          (d) The Indemnity Provider shall be responsible for preparing and
     filing any real and personal property or ad valorem tax returns in respect
     of each Property and any other tax returns required for the Owner Trustee
     respecting the transactions described in the Operative Agreements. The
     Indemnity Provider shall undertake reasonable diligence to determine if any
     other report or tax return shall be required to be made with respect to any
     obligations of the Indemnity Provider under or arising out of subsection
     (a) and, with respect to such other reports or tax returns of which the
     Indemnity Provider has knowledge, the Indemnity Provider, at its sole cost
     and expense, shall notify the relevant Indemnified Person of such
     requirement and (except if such Indemnified Person notifies the Indemnity
     Provider that such Indemnified Person intends to prepare and file such
     report or return) (A) to the extent required or permitted by and consistent
     with Legal Requirements, make and file in the Indemnity Provider's name
     such return, statement or report; and (B) in the case of any other such
     return, statement or report required to be made in the name of such
     Indemnified Person, advise such Indemnified Person of such fact and prepare
     such return, statement or report for filing by such Indemnified Person or,
     where such return, statement or report shall be required to reflect items
     in addition to any obligations of the Indemnity Provider under or arising
     out of subsection (a), provide such Indemnified Person at the Indemnity
     Provider's expense with information sufficient to permit such return,
     statement or report to be properly made with respect to any obligations of
     the Indemnity Provider under or arising out of subsection (a).  Such
     Indemnified Person shall, upon the Indemnity Provider's request and at the
     Indemnity Provider's expense, provide any data maintained by such
     Indemnified Person with respect to each Property which the Indemnity
     Provider may reasonably require to prepare any required tax returns or
     reports.

          (e) As between the Indemnity Provider on one hand, and each Financing
     Party on the other hand, the Indemnity Provider shall be responsible for,
     and the Indemnity Provider shall indemnify and hold harmless each Financing
     Party (without duplication of any indemnification required by subsection
     (a)) on an After Tax Basis against, any obligation for United States or
     foreign withholding taxes or 

                                       44
<PAGE>
 
     similar levies, imposts, charges, fees, deductions or withholdings
     (collectively, "Withholdings") imposed in respect of the interest payable
     on the Notes, Holder Yield payable on the Certificates or with respect to
     any other payments under the Operative Agreement (all such payments being
     referred to herein as "Exempt Payments" to be made without deduction,
     withholding or set off) (and, if any Financing Party receives a demand for
     such payment from any taxing authority or a Withholding is otherwise
     required with respect to any Exempt Payment, the Indemnity Provider shall
     discharge such demand on behalf of such Financing Party); provided,
     however, that the obligation of the Indemnity Provider under this Section
     11.2(e) shall not apply to:

               (i) Withholdings on any Exempt Payment to any Financing Party
          which is a non-U.S. Person unless such Financing Party is, on the date
          hereof (or on the date it becomes a Financing Party hereunder) and on
          the date of any change in the principal place of business or the
          lending office of such Financing Party, entitled to submit a Form 1001
          (relating to such Financing Party and entitling it to a complete
          exemption from Withholding on such Exempt Payment) or Form 4224 or is
          otherwise subject to exemption from Withholding with respect to such
          Exempt Payment (except where the failure of the exemption results from
          a change in the principal place of business of the Lessee; provided,
          if a failure of exemption for any Financing Party results from a
          change in the principal place of business or lending office of any
          other Financing Party, then such other Financing Party shall be liable
          for any Withholding or indemnity with respect thereto), or

               (ii) Any U.S. Taxes imposed solely by reason of the failure by a
          non-U.S. Person to comply with applicable certification, information,
          documentation or other reporting requirements concerning the
          nationality, residence, identity or connections with the United States
          of America of such non-U.S. Person if such compliance is required by
          statute or regulation of the United States of America as a
          precondition to relief or exemption from such U.S. Taxes.

     For the purposes of this Section 11.2(e), (A) "U.S. Person" shall mean a
     citizen, national or resident of the United States of America, a
     corporation, partnership or other entity created or organized in or under
     any laws of the United States of America or any State thereof, or any
     estate or trust that is subject to Federal income taxation regardless of
     the source of its income, (B) "U.S. Taxes" shall mean any present or future
     tax, assessment or other charge or levy imposed by or on behalf of the
     United States of America or any taxing authority thereof or therein, (C)
     "Form 1001" shall mean Form 1001 (Ownership, Exemption, or Reduced Rate
     Certificate) of the Department of the Treasury of the United States of
     America and (D) "Form 4224" shall mean Form 4224 (Exemption from
     Withholding of Tax on Income Effectively Connected with the Conduct of a
     Trade or Business in the United States) of the Department of Treasury of
     the United States of America (or in relation to

                                       45
<PAGE>
 
     either such Form such successor and related forms as may from time to time
     be adopted by the relevant taxing authorities of the United States of
     America to document a claim to which such Form relates). Each of the Forms
     referred to in the foregoing clauses (C) and (D) shall include such
     successor and related forms as may from time to time be adopted by the
     relevant taxing authorities of the United States of America to document a
     claim to which such Form relates.

          If a Financing Party or an Affiliate with whom such Financing Party
     files a consolidated tax return (or equivalent) subsequently receives the
     benefit in any country of a tax credit or an allowance resulting from U.S.
     Taxes with respect to which it has received a payment of an additional
     amount under this Section 11.2(e), such Financing Party will pay to the
     Indemnity Provider such part of that benefit as in the reasonable opinion
     of such Financing Party will leave it (after such payment) in a position no
     more and no less favorable than it would have been in if no additional
     payment had been required to be paid, provided, always that (i) such
     Financing Party will be the sole judge of the amount of any such benefit
     and of the date on which it is received, (ii) such Financing Party will
     have the absolute discretion as to the order and manner in which it employs
     or claims tax credits and allowances available to it and (iii) such
     Financing Party will not be obliged to disclose to the Borrower any
     information regarding its tax affairs or tax computations.

          Each non-U.S. Person that shall become a Financing Party after the
     date hereof shall, upon the effectiveness of the related transfer or
     otherwise upon becoming a Financing Party hereunder, be required to provide
     all of the forms and statements referenced above or other evidences of
     exemption from Withholdings.

          (f) If a written Claim is made against any Indemnified Person or if
     any proceeding shall be commenced against such Indemnified Person
     (including without limitation a written notice of such proceeding), for any
     Impositions, the provisions in Section 11.1 relating to notification and
     rights to contest shall apply; provided, however, that the Indemnity
     Provider shall have the right to conduct and control such contest only if
     such contest involves a Tax other than a Tax on net income of the
     Indemnified Person and can be pursued independently from any other
     proceeding involving a Tax liability of such Indemnified Person.

     11.3.  INCREASED COSTS, ILLEGALITY, ETC.

          (a) If, due to either (i) the introduction of, or any change in or in
     the interpretation of, any law or regulation or (ii) the compliance with
     any guideline or request hereafter adopted, promulgated or made by any
     central bank or other governmental authority (whether or not having the
     force of law), there shall be any increase in the cost to any Financing
     Party of agreeing to make or making, funding or maintaining Advances, then
     the Lessee shall from time to time, promptly after demand by such Financing
     Party (with a copy of such demand to the Agent but 

                                       46
<PAGE>
 
     subject to the terms of Section 2.11 of the Credit Agreement and 3.9 of the
     Trust Agreement, as the case may be), pay to the Agent for the account of
     such Financing Party additional amounts sufficient to compensate such
     Financing Party for such increased cost. A certificate setting forth in
     reasonable detail the amount of such increased cost and the basis therefor,
     submitted to the Lessee and the Agent by such Financing Party, shall be
     presumptively correct for all purposes, absent manifest error.

          (b) If any Financing Party determines that compliance with any law or
     regulation or any guideline or request from any central bank or other
     governmental authority (whether or not having the force of law, which in
     the case of all of the foregoing in this sentence is promulgated or made
     after the date hereof) affects or would affect the amount of capital
     required or expected to be maintained by such Financing Party or any
     corporation controlling such Financing Party and that the amount of such
     capital is increased by or based upon the existence of such Financing
     Party's commitment to make Advances or upon the Advances, then, promptly
     after demand by such Financing Party (with a copy of such demand to the
     Agent but subject to the terms of Section 2.11 of the Credit Agreement and
     3.9 of the Trust Agreement), the Lessee shall pay to the Agent for the
     account of such Financing Party, from time to time as specified by such
     Financing Party, additional amounts sufficient to compensate such Financing
     Party or such corporation in the light of such circumstances, to the extent
     that such Financing Party reasonably determines such increase in capital to
     be allocable to the existence of such Financing Party's commitment to make
     such Advances.  A certificate setting forth in reasonable detail such
     amounts and the basis therefor submitted to the Lessee and the Agent by
     such Financing Party shall be presumptively correct for all purposes,
     absent manifest error.

          (c) Without limiting the effect of the foregoing, the Lessee shall pay
     to each Financing Party on the last day of the Interest Period therefor so
     long as such Financing Party is maintaining reserves against "Eurocurrency
     liabilities" under Regulation D an additional amount (determined by such
     Financing Party and notified to the Lessee through the Agent) equal to the
     product of the following for each Eurodollar Loan or Eurodollar Holder
     Advance, as the case may be, for each day during such Interest Period:

               (i) the principal amount of such Eurodollar Loan or Eurodollar
          Holder Advance, as the case may be, outstanding on such day; and

               (ii) the remainder of (x) a fraction the numerator of which is
          the rate (expressed as a decimal) at which interest accrues on such
          Eurodollar Loan or Eurodollar Holder Advance, as the case may be, for
          such Interest Period as provided in the Credit Agreement or the Trust
          Agreement, as the case may be (less the Applicable Margin), and the
          denominator of which is one (1) minus the effective rate (expressed as
          a decimal) at which such 

                                       47
<PAGE>
 
          reserve requirements are imposed on such Financing Party on such day
          minus (y) such numerator; and

               (iii)     1/360.

          (d) Without affecting its rights under Sections 11.3(a), 11.3(b) or
     11.3(c) or any other provision of any Operative Agreement, each Financing
     Party agrees that if there is any increase in any cost to or reduction in
     any amount receivable by such Financing Party with respect to which the
     Lessee would be obligated to compensate such Financing Party pursuant
     to Sections 11.3(a) or 11.3(b), such Financing Party shall use reasonable
     efforts to select an alternative office for Advances which would not result
     in any such increase in any cost to or reduction in any amount receivable
     by such Financing Party; provided, however, that no Financing Party shall
     be obligated to select an alternative office for Advances if such Financing
     Party determines that (i) as a result of such selection such Financing
     Party would be in violation of any applicable law, regulation, treaty, or
     guideline, or would incur additional costs or expenses or (ii) such
     selection would be inadvisable for regulatory reasons or materially
     inconsistent with the interests of such Financing Party.

          (e) With reference to the obligations of the Lessee set forth in
     Sections 11.3(a) through 11.3(d), the Lessee shall not have any obligation
     to pay to any Financing Party amounts owing under such Sections for any
     period which is more than one (1) year prior to the date upon which the
     request for payment therefor is delivered to the Lessee.

          (f) Notwithstanding any other provision of this Agreement, if any
     Financing Party shall notify the Agent that the introduction of or any
     change in or in the interpretation of any law or regulation makes it
     unlawful, or any central bank or other governmental authority asserts that
     it is unlawful, for any Financing Party to perform its obligations
     hereunder to make or maintain Eurodollar Loans or Eurodollar Holder
     Advances, as the case may be, then (i) each Eurodollar Loan or Eurodollar
     Holder Advance, as the case may be, will automatically, at the earlier of
     the end of the Interest Period for such Eurodollar Loan or Eurodollar
     Holder Advance, as the case may be, or the date required by law, convert
     into an ABR Loan or an ABR Holder Advance, as the case may be, and (iii)
     the obligation of the Financing Parties to make, convert or continue
     Eurodollar Loans or Eurodollar Holder Advances, as the case may be, shall
     be suspended until the Agent shall notify the Lessee that such Financing
     Party has determined that the circumstances causing such suspension no
     longer exist.

     11.4.  FUNDING/CONTRIBUTION INDEMNITY.

     Subject to the provisions of Section 2.11(a) of the Credit Agreement and
3.9(a) of the Trust Agreement, as the case may be, the Lessee agrees to
indemnify each Financing Party 

                                       48
<PAGE>
 
and to hold each Financing Party harmless from any l oss or reasonable expense
which such Financing Party may sustain or incur as a consequence of (a) any
default not attributable to such Financing Party in connection with the drawing
of funds for any Advance, (b) any default in making any prepayment after a
notice thereof has been given in accordance with the provisions of the Operative
Agreements or (c) the making of a voluntary or involuntary prepayment of
Eurodollar Loans or Eurodollar Holder Advances, as the case may be, on a day
which is not the last day of an Interest Period with respect thereto. Such
indemnification shall be in an amount equal to the excess, if any, of (x) the
amount of interest or Holder Yield, as the case may be, which would have accrued
on the amount so prepaid, or not so borrowed, accepted, converted or continued
for the period from the date of such prepayment or of such failure to borrow,
accept, convert or continue to the last day of such Interest Period (or, in the
case of a failure to borrow, accept, convert or continue, the Interest Period
that would have commenced on the date of such failure) in each case at the
applicable Eurodollar Rate plus the Applicable Margin for such Loan or Holder
Advance, as the case may be, for such Interest Period over (y) the amount of
interest (as determined by such Financing Party in its reasonable judgment)
which would have accrued to such Financing Party on such amount by (i) (in the
case of the Lenders) reemploying such funds in loans of the same type and amount
during the period from the date of prepayment or failure to borrow to the last
day of the then applicable Interest Period (or, in the case of a failure to
borrow, the Interest Period that would have commenced on the date of such
failure) and (ii) (in the case of the Holders) placing such amount on deposit
for a comparable period with leading banks in the relevant interest rate market.
This covenant shall survive the termination of the Operative Agreements and the
payment of all other amounts payable hereunder.

     11.5 EXPRESS INDEMNIFICATION FOR ORDINARY NEGLIGENCE, STRICT LIABILITY,
          ETC.

     WITHOUT LIMITING THE GENERALITY OF THE INDEMNIFICATION PROVISIONS OF ANY
AND ALL OF THE OPERATIVE AGREEMENTS, EACH PERSON PROVIDING INDEMNIFICATION OF
ANOTHER PERSON UNDER ANY OPERATIVE AGREEMENT HEREBY FURTHER EXPRESSLY RELEASES
EACH BENEFICIARY OF ANY SUCH INDEMNIFICATION FROM ALL CLAIMS FOR LOSS OR DAMAGE,
DESCRIBED IN ANY OPERATIVE AGREEMENT, CAUSED BY ANY ACT OR OMISSION ON THE PART
OF ANY SUCH BENEFICIARY ATTRIBUTABLE TO THE ORDINARY NEGLIGENCE (WHETHER SOLE OR
CONTRIBUTORY) OR STRICT LIABILITY OF ANY SUCH BENEFICIARY, AND INDEMNIFIES,
EXONERATES AND HOLDS EACH SUCH BENEFICIARY FREE AND HARMLESS FROM AND AGAINST
ANY AND ALL ACTIONS, CAUSES OF ACTION, SUITS, CLAIMS, LOSSES, COSTS,
LIABILITIES, DAMAGES AND EXPENSES (INCLUDING WITHOUT LIMITATION ATTORNEY'S FEES
AND EXPENSES), DESCRIBED ABOVE, INCURRED BY ANY SUCH BENEFICIARY (IRRESPECTIVE
OF WHETHER ANY SUCH BENEFICIARY IS A PARTY TO THE ACTION FOR WHICH
INDEMNIFICATION UNDER THIS AGREEMENT OR ANY OTHER OPERATIVE AGREEMENT IS SOUGHT)
ATTRIBUTABLE TO THE ORDINARY NEGLIGENCE

                                       49
<PAGE>
 
(WHETHER SOLE OR CONTRIBUTORY) OR STRICT LIABILITY OF ANY SUCH BENEFICIARY.


                          SECTION 12.  MISCELLANEOUS.

     12.1.  SURVIVAL OF AGREEMENTS.

     The representations, warranties, covenants, indemnities and agreements of
the parties provided for in the Operative Agreements, and the parties'
obligations under any and all thereof, shall survive the execution and delivery
of this Agreement, the transfer of any Property to the Owner Trustee, the
acquisition of any Property (or any of its components), the construction of any
Improvements, the Completion of any Property, any disposition of any interest of
the Owner Trustee in any Property or any interest of the Holders in the Trust
Estate, the payment of the Notes and any disposition of the Notes and shall be
and continue in effect notwithstanding any investigation made by any party and
the fact that any party may waive compliance with any of the other terms,
provisions or conditions of any of the Operative Agreements. Except as otherwise
expressly set forth herein or in other Operative Agreements, the indemnities of
the parties provided for in the Operative Agreements shall survive the
expiration or termination of any thereof.

     12.2.  NOTICES.

     All notices required or permitted to be given under or otherwise given in
connection with any Operative Agreement shall be in writing. Notices may be
served by certified or registered mail, postage paid with return receipt
requested; by private courier, prepaid; by telex, facsimile, or other
telecommunication device capable of transmitting or creating a written record;
or personally. Mailed notices shall be deemed delivered five (5) days after
mailing, properly addressed. Couriered notices shall be deemed delivered when
delivered as addressed, or if the addressee refuses delivery, when presented for
delivery notwithstanding such refusal. Telex or telecommunicated notices shall
be deemed delivered when receipt is either confirmed by confirming transmission
equipment or acknowledged by the addressee or its office. Personal delivery
shall be effective when accomplished. Unless a party changes its address by
giving notice to the other party as provided herein, notices shall be delivered
to the parties at the following addresses:

                                       50
<PAGE>
 
          If to the Construction Agent or the Lessee, to such entity at the
     following address:

                    AOR Synthetic Real Estate, Inc.
                    c/o American Oncology Resources, Inc.
                    16825 Northchase Drive
                    Suite 1300
                    Houston, Texas  77060
                    Attention:  L. Fred Pounds,
                                Chief Financial Officer
                    Telephone:  (713) 873-2674
                    Telecopy:   (713) 873-7762
 
               If to the Guarantor, to such entity at the following address:
 
                    American Oncology Resources, Inc.
                    16825 Northchase Drive
                    Suite 1300
                    Houston, Texas  77060
                    Attention:  L. Fred Pounds,
                                Chief Financial Officer
                    Telephone:  (713) 873-2674
                    Telecopy:   (713) 873-7762
 
 

               If to any Tranche A Guarantor, to such entity c/o AOR at the
               following address:
                    [Name of applicable Tranche A Guarantor]
                    c/o American Oncology Resources, Inc.
                    16825 Northchase Drive
                    Suite 1300
                    Houston, Texas  77060
                    Attention:  L. Fred Pounds,
                                Chief Financial Officer
                    Telephone:  (713) 873-2674
                    Telecopy:   (713) 873-7762
 

                                       51
<PAGE>
 
with a copy to:
 
                    Mayor, Day, Caldwell & Keeton, L.L.P.
                    700 Louisiana, Suite 1900
                    Houston, Texas  77002
                    Attention:  Geoffrey K. Walker
                    Telephone:  (713) 225-7020
                    Telecopy:   (713) 225-7047
 
          If to the Owner Trustee, to it at the
           following address:
 
                    First Security Bank, National Association
                    79 South Main Street
                    Salt Lake City, Utah 84111
                    Attention:  Val T. Orton,
                                Vice President
                    Telephone:  (801) 246-5300
                    Telecopy:   (801) 246-5053

          If to the Holders, to each such Holder at the address set forth for
     such Holder on Schedule I of the Trust Agreement.

          If to the Agent, to it at the following address:

                    First Union National Bank
                    c/o First Union Capital Markets Group
                    DC-6
                    301 South College Street
                    Charlotte, North Carolina  28288-0166
                    Attention:     Jane O. Hurley,
                                   Capital Markets Services
                    Telephone:     (704) 383-3812
                    Telecopy:      (704) 383-7989


               If to any Lender, to it at the address set forth for such Lender
     in Schedule 1.1 of the Credit Agreement.

          From time to time any party may designate additional parties and/or
     another address for notice purposes by notice to each of the other parties
     hereto.  Each notice hereunder shall be effective upon receipt or refusal
     thereof.

                                       52
<PAGE>
 
     12.3.  COUNTERPARTS.
 
     This Agreement may be executed by the parties hereto in separate
counterparts, each of which when so executed and delivered shall be an original,
but all such counterparts shall together constitute but one (1) and the same
instrument.

     12.4.  TERMINATIONS, AMENDMENTS, WAIVERS, ETC.; UNANIMOUS VOTE MATTERS.

     Each Operative Agreement may be terminated, amended, supplemented, waived
or modified only by an instrument in writing signed by, subject to Article VIII
of the Trust Agreement regarding termination of the Trust Agreement, the
Majority Secured Parties and each Credit Party (to the extent such Credit Party
is a party to such Operative Agreement); provided, to the extent no Default or
Event of Default shall have occurred and be continuing, the Majority Secured
Parties shall not amend, supplement, waive or modify any provision of any
Operative Agreement in such a manner as to adversely affect the rights of any
Credit Party without the prior written consent (to be determined in good faith
with such determination not to be unreasonably delayed) of such Credit Party. In
addition, (a) the Unanimous Vote Matters shall require the consent of each
Lender and each Holder affected by such matter and (b) any provision of any
Operative Agreement incorporated by reference or otherwise referenced in a
second Operative Agreement shall remain, respecting such second Operative
Agreement, in its original form without regard to any such termination,
amendment, supplement, waiver or modification in the first Operative Agreement
except if such termination, amendment, supplement, waiver or modification has
been agreed to by an instrument in writing signed by, subject to Article VIII of
the Trust Agreement regarding termination of the Trust Agreement, the Majority
Secured Parties and each Credit Party (to the extent such Credit Party is a
party to such Operative Agreement).

     Notwithstanding the foregoing, no such termination, amendment, supplement,
waiver or modification shall, without the consent of the Agent and, to the
extent affected thereby, each Lender and each Holder (collectively, the
"Unanimous Vote Matters") (i) reduce the amount of any Note or any Certificate,
extend the scheduled date of maturity of any Note, extend the scheduled
Expiration Date, extend any date of payment of any Note or Certificate, reduce
the stated rate of interest payable on any Note or reduce the stated Holder
Yield payable on any Certificate (other than as a result of waiving the
applicability of any post-default increase in interest rates or Holder Yields),
modify the priority of any Lien in favor of the Agent under any Security
Document, subordinate any obligation owed to any Lender or Holder, reduce any
Lender Facility Fees or any Holder Facility Fees payable under the Participation
Agreement, extend the scheduled date of payment of any Lender Facility Fees or
any Holder Facility Fees or increase the amount or extend the expiration date of
any Lender's Commitment or the Holder Commitment of any Holder, or (ii)
terminate, amend, supplement, waive or modify any provision of this Section 12.4
or reduce the percentages specified in the definitions of Majority Lenders,
Majority Holders or Majority Secured Parties, or consent to the assignment or
transfer by the Owner Trustee of any of its rights and obligations under any
Credit Document or release a material portion of the Collateral (except in
accordance with Section 8.8) or release the Construction Agent, the Lessee or
AOR from their respective obligations under any Operative Agreement, release all
or substantially all of the Tranche A Guarantors from their obligations 

                                       53
<PAGE>
 
under Section 8B of the Credit Agreement or consent to the assignment or
transfer by any Credit Party (except with respect to the rights of Lessee under
Section 25.2 of the Lease) of its rights or obligations under the Operative
Agreements, or (iii) terminate, amend, supplement, waive or modify any provision
of Section 7 of the Credit Agreement, or (iv) permit Advances for Work in excess
of the Construction Budget, or (v) eliminate the automatic option under Section
5.3(b) of the Agency Agreement requiring that the Construction Agent pay certain
liquidated damages in exchange for the conveyance of a Property to the
Construction Agent. Any such termination, amendment, supplement, waiver or
modification shall apply equally to each of the Lenders and the Holders and
shall be binding upon all the parties to this Agreement. In the case of any
waiver, each party to this Agreement shall be restored to its former position
and rights under the Operative Agreements prior to the event or condition so
waived, and any Default or Event of Default waived shall be deemed to be cured
and not continuing; but no such waiver shall extend to any subsequent or other
Default or Event of Default, or impair any right consequent thereon.

     If at a time when the conditions precedent set forth in the Operative
Agreements to any Loan are, in the opinion of the Majority Lenders, satisfied,
any Lender shall fail to fulfill its obligations to make such Loan (any such
Lender, a "Defaulting Lender") then, for so long as such failure shall continue,
the Defaulting Lender shall (unless the Lessee and the Construction Agent and
the Majority Lenders, determined as if the Defaulting Lender were not a
"Lender", shall otherwise consent in writing) be deemed for all purposes
relating to terminations, amendments, supplements, waivers or modifications
under the Operative Agreements to have no Loans, shall not be treated as a
"Lender" when performing the computation of Majority Lenders or Majority Secured
Parties, and shall have no rights under this Section 12.4; provided, that any
action taken pursuant to the second paragraph of this Section 12.4 shall not be
effective as against the Defaulting Lender unless it otherwise consents.

     If at a time when the conditions precedent set forth in the Operative
Agreements to any Holder Advance are, in the opinion of the Majority Holders,
satisfied, any Holder shall fail to fulfill its obligations to make such Holder
Advance (any such Holder, a "Defaulting Holder") then, for so long as such
failure shall continue, the Defaulting Holder shall (unless the Lessee and the
Construction Agent and the Majority Holders, determined as if the Defaulting
Holder were not a "Holder", shall otherwise consent in writing) be deemed for
all purposes relating to terminations, amendments, supplements, waivers or
modifications under the Operative Agreements to have no Holder Advances, shall
not be treated as a "Holder" when performing the computation of Majority Holders
or Majority Secured Parties, and shall have no rights under this Section 12.4;
provided, that any action taken pursuant to the second paragraph of this Section
12.4 shall not be effective as against the Defaulting Holder unless it otherwise
consents.

     12.5.  HEADINGS, ETC.

     The Table of Contents and headings of the various Articles and Sections of
this Agreement are for convenience of reference only and shall not modify,
define, expand or limit any of the terms or provisions hereof.

                                       54
<PAGE>
 
     12.6.  PARTIES IN INTEREST.

     Except as expressly provided herein, none of the provisions of this
Agreement are intended for the benefit of any Person except the parties hereto.

     12.7.  GOVERNING LAW; SUBMISSION TO JURISDICTION; WAIVER OF JURY
            TRIAL; VENUE; ARBITRATION.

          (a) THIS AGREEMENT AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES
     HEREUNDER SHALL BE GOVERNED BY AND CONSTRUED AND INTERPRETED AND ENFORCED
     IN ACCORDANCE WITH THE LAWS OF THE STATE OF NORTH CAROLINA.  Any legal
     action or proceeding with respect to this Agreement or any other Operative
     Agreement may be brought in the courts of the State of North Carolina in
     Mecklenburg County or of the United States for the Western District of the
     State of North Carolina, and, by execution and delivery of this Agreement,
     each of the parties to this Agreement hereby irrevocably accepts for itself
     and in respect of its property, generally and unconditionally, the
     nonexclusive jurisdiction of such courts.  Each of the parties to this
     Agreement further irrevocably consents to the service of process out of any
     of the aforementioned courts in any such action or proceeding by the
     mailing of copies thereof by registered or certified mail, postage prepaid,
     to it at the address set out for notices pursuant to Section 12.2, such
     service to become effective three (3) days after such mailing.  Nothing
     herein shall affect the right of any party to serve process in any other
     manner permitted by Law or to commence legal proceedings or to otherwise
     proceed against any party in any other jurisdiction.

          (b) EACH OF THE PARTIES HERETO IRREVOCABLY AND UNCONDITIONALLY, TO THE
     FULLEST EXTENT ALLOWED BY APPLICABLE LAW, WAIVES TRIAL BY JURY IN ANY LEGAL
     ACTION OR PROCEEDING RELATING TO THIS AGREEMENT, ANY OTHER OPERATIVE
     AGREEMENT AND FOR ANY COUNTERCLAIM THEREIN.

          (c) To the fullest extent allowed by applicable law, each of the
     parties to this Agreement hereby irrevocably waives any objection which it
     may now or hereafter have to the laying of venue of any of the aforesaid
     actions or proceedings arising out of or in connection with this Agreement
     or any other Operative Agreement brought in the courts referred to in
     subsection (a) above and hereby further irrevocably waives and agrees not
     to plead or claim in any such court that any such action or proceeding
     brought in any such court has been brought in an inconvenient forum.

          (d) Notwithstanding the provisions of Section 12.7(a) or of any other
     Operative Agreement to the contrary, upon demand of any party hereto,
     whether made before or after institution of any judicial proceeding
     (subject to the following limitation), any dispute, claim or controversy
     arising out of, connected with or relating to this Agreement or any other
     Operative Agreement ("Disputes") between or among parties to this Agreement
     and/or any other Operative Agreement, or any of them, shall be resolved 

                                       55
<PAGE>
 
     by binding arbitration as provided herein; provided, however, that no party
     may demand arbitration in any judicial proceeding to which it is a party
     more than ninety (90) days from the later of (i) its commencement of such
     proceeding or (ii) the date it is served with a complaint, counterclaim or
     third-party claim in such proceeding. Disputes may include, without
     limitation, tort claims, counterclaims, claims brought as class actions,
     claims arising from this Agreement and/or any other Operative Agreement
     executed in the future, or claims arising out of or connected with the
     transactions contemplated by this Agreement and/or any other Operative
     Agreement. Arbitration shall be conducted under and governed by the
     Commercial Financial Disputes Arbitration Rules (the "Arbitration Rules")
     of the American Arbitration Association (the "AAA"), as in effect from time
     to time, and Title 9 of the U.S. Code, as amended. All arbitration hearings
     shall be conducted in the city in which the principal office of either the
     Agent or the Borrower is located. The expedited procedures set forth in
     Rule 51 et seq. of the Arbitration Rules shall be applicable to claims of
     less than $1,000,000. All applicable statutes of limitation shall apply to
     any Dispute. All arbitrations commenced with respect to any of the
     Operative Agreements shall be consolidated for hearing before the same
     panel of arbitrators as prescribed herein. Any attorney-client privilege or
     other protection against disclosure of confidential information, including
     without limitation any protection afforded the work product of any
     attorney, that would otherwise be claimed by any party shall be available
     to and may be claimed by any such party in any arbitration proceeding. A
     judgment upon the award may be entered in any court having jurisdiction.
     The panel from which all arbitrators are selected shall be comprised of
     licensed attorneys. The single arbitrator selected for expedited procedure
     shall be a retired judge from the highest court of general jurisdiction,
     state or federal, of the state where the hearing will be conducted.
     Notwithstanding the foregoing, this arbitration provision does not apply to
     Disputes under or related to Interest Rate Protection Agreements. An
     arbitration arising from an Interest Rate Protection Agreement shall not be
     consolidated with any other arbitration hereunder without the consent of
     all parties to the arbitrations that are proposed to be consolidated.

          Notwithstanding the preceding binding arbitration provisions, the
     parties hereto agree to preserve, without diminution, certain remedies that
     any party hereto may employ or exercise freely, either alone, in
     conjunction with or during a Dispute.  Any party hereto shall have the
     right to proceed in any court of proper jurisdiction or by self-help to
     exercise or prosecute the following remedies, as applicable: (a) all rights
     to foreclose against any Collateral by exercising a power of sale granted
     pursuant to any of the Operative Agreements or under applicable law other
     than judicial foreclosure and sale, including a proceeding to confirm the
     sale; (b) all rights of self-help, including peaceful occupation of real
     property and collection of rents, setoff, and peaceful possession of
     personal property; (c) obtaining provisional or ancillary remedies,
     including injunctive relief, sequestration, garnishment, attachment,
     appointment of a receiver and filing an involuntary bankruptcy proceeding;
     and (d) when applicable, a judgment by confession of judgment.
     Preservation of these remedies does not limit the power of an arbitrator to
     grant similar remedies that may be requested by a party in a Dispute.

                                       56
<PAGE>
 
     12.8.  SEVERABILITY.

     Any provision of this Agreement that is prohibited or unenforceable in any
jurisdiction shall, as to such jurisdiction, be ineffective to the extent of
such prohibition or unenforceability without invalidating the remaining
provisions hereof, and any such prohibition or unenforceability in any
jurisdiction shall not invalidate or render unenforceable such provision in any
other jurisdiction.

     12.9.  LIABILITY LIMITED.

            (a) The Lenders, the Agent, the Credit Parties, the Owner Trustee
     and the Holders each acknowledge and agree that the Owner Trustee is
     (except as otherwise expressly provided herein or therein) entering into
     this Agreement and the other Operative Agreements to which it is a party
     (other than the Trust Agreement and to the extent otherwise provided in
     Section 6.1 of this Agreement), solely in its capacity as trustee under the
     Trust Agreement and not in its individual capacity and that the Trust
     Company shall not be liable or accountable under any circumstances
     whatsoever in its individual capacity for or on account of any statements,
     representations, warranties, covenants or obligations stated to be those of
     the Owner Trustee, except for its own gross negligence or willful
     misconduct and as otherwise expressly provided herein or in the other
     Operative Agreements.

          (b) Anything to the contrary contained in this Agreement, the Credit
     Agreement, the Notes or in any other Operative Agreement notwithstanding,
     no officer, director or shareholder (other than any Credit Party) of any
     party to any Operative Agreement (but excluding all Credit Parties which
     shall be fully liable for all their obligations under the Operative
     Agreements) shall be personally liable in any respect for any liability or
     obligation arising hereunder or in any other Operative Agreement including
     without limitation the payment of the principal of, or interest on, the
     Notes, or for monetary damages for the breach of performance of any of the
     covenants contained in the Credit Agreement, the Notes, this Agreement, the
     Security Agreement or any of the other Operative Agreements.  The Lenders,
     the Holders and the Agent agree that, in the event any remedies under any
     Operative Agreement are pursued, neither the Lenders, the Holders nor the
     Agent shall have any recourse against any officer, director or shareholder
     (other than any Credit Party) of any party to any Operative Agreement (but
     excluding all Credit Parties which shall be fully liable for all their
     obligations under the Operative Agreements), for any deficiency, loss or
     Claim for monetary damages or otherwise resulting therefrom and recourse
     shall be had solely and exclusively against the Trust Estate (excluding
     Excepted Payments) and the Credit Parties (with respect to the Credit
     Parties' obligations under the Operative Agreements); but nothing contained
     herein shall be taken to prevent recourse against or the enforcement of
     remedies against the Trust Estate (excluding Excepted Payments) in respect
     of any and all liabilities, obligations and undertakings contained herein
     and/or in any other Operative Agreement.  Notwithstanding the provisions of
     this Section, nothing in any Operative Agreement shall:  (i) constitute a
     waiver, release or discharge of any indebtedness or obligation 

                                       57
<PAGE>
 
     evidenced by the Notes and/or the Certificates arising under any Operative
     Agreement or secured by any Operative Agreement, but the same shall
     continue until paid or discharged; (ii) relieve any Exculpated Person from
     liability and responsibility for (but only to the extent of the damages
     arising by reason of): active waste knowingly committed by any Exculpated
     Person with respect to any Property, any fraud, gross negligence or willful
     misconduct on the part of any Exculpated Person; (iii) relieve any
     Exculpated Person from liability and responsibility for (but only to the
     extent of the moneys misappropriated, misapplied or not turned over) (A)
     except for Excepted Payments, misappropriation or misapplication by the
     Lessor (i.e., application in a manner contrary to any of the Operative
     Agreements) of any insurance proceeds or condemnation award paid or
     delivered to the Lessor by any Person other than the Agent, (B) except for
     Excepted Payments, any deposits or any escrows or amounts owed by the
     Construction Agent under the Agency Agreement held by the Lessor or (C)
     except for Excepted Payments, any rent or other income received by the
     Lessor from any Credit Party that is not turned over to the Agent; or (iv)
     affect or in any way limit the Agent's rights and remedies under any
     Operative Agreement with respect to the Rents and rights and powers of the
     Agent under the Operative Agreements or to obtain a judgment against the
     Lessee's interest in the Properties or the Agent's rights and powers to
     obtain a judgment against the Lessor or any Credit Party (provided, that no
     deficiency judgment or other money judgment shall be enforced against any
     Exculpated Person except to the extent of the Lessor's interest in the
     Trust Estate (excluding Excepted Payments) or to the extent the Lessor may
     be liable as otherwise contemplated in clauses (ii) and (iii) of this
     Section 12.9(b)).

     12.10.  RIGHTS OF THE LESSEE.

     If at any time all obligations (i) of the Owner Trustee under and in
accordance with the Credit Agreement, the Security Documents and the other
Operative Agreements and (ii) of the Credit Parties under the Operative
Agreements have in each case been satisfied or discharged in full, then the
Credit Parties shall be entitled to (a) terminate the Lease and the guaranty
obligations of the Guarantor and the Tranche A Guarantors arising under and in
accordance with the Credit Agreement and (b) receive all amounts then held under
the Operative Agreements and all proceeds with respect to any of the Properties.
Upon the termination of the Lease and the guaranty obligations of the Guarantor
and the Tranche A Guarantors pursuant to the foregoing clause (a), the Lessor
shall transfer to the Lessee or its designee all of its right, title and
interest free and clear of the Lien of the Lease, the Lien of the Security
Documents and all Lessor Liens in and to any Properties then subject to the
Lease and any amounts or proceeds referred to in the foregoing clause (b) shall
be paid over to the Lessee.

     12.11.  FURTHER ASSURANCES.

     The parties hereto shall promptly cause to be taken, executed, acknowledged
or delivered, at the sole expense of the Lessee, all such further acts,
conveyances, documents and assurances as the other parties may from time to time
reasonably request in order to carry out and effectuate the intent and purposes
of this Participation Agreement, the other Operative Agreements and the

                                       58
<PAGE>
 
transactions contemplated hereby and thereby (including without limitation the
preparation, execution and filing of any and all Uniform Commercial Code
financing statements, filings of Mortgage Instruments and other filings or
registrations which the parties hereto may from time to time reasonably request
to be filed or effected). The Lessee, at its own expense, shall take such action
(including without limitation any action specified in the preceding sentence),
as the Owner Trustee shall so request in order to maintain and protect all
security interests provided for hereunder or under any other Operative
Agreement.

     12.12.  CALCULATIONS UNDER OPERATIVE AGREEMENTS.

     The parties hereto agree that all calculations and numerical determinations
to be made under the Operative Agreements by the Owner Trustee shall be made by
the Agent and that such calculations and determinations shall be presumptively
correct on the parties hereto in the absence of manifest error.

    12.13.  CONFIDENTIALITY.

     Each of the Agent, the Lessor, each Lender and each Holder agrees to take
normal and reasonable precautions and exercise due care to maintain the
confidentiality of all non-public confidential information provided in
connection with this Agreement or any other Operative Agreement and agrees and
undertakes that it shall not use any such information for any purpose or in any
manner other than pursuant to the terms contemplated by this Agreement. The
Agent, the Lessor, any Lender or any Holder may disclose such information (a) at
the request of any bank regulatory authority or in connection with an
examination of the Agent, the Lessor, such Lender or such Holder by any such
authority, (b) pursuant to subpoena or other court process, (c) when required to
do so in accordance with the provisions of any applicable law or regulation, (d)
at the express direction of any agency of any State of the United States of
America or of any other jurisdiction in which the Agent, the Lessor, such Lender
or such Holder conducts its business, (e) to the Agent's, the Lessor's, such
Lender's or such Holder's independent auditors and other professional advisors
that have a reasonable need or basis for access thereto and (f) in connection
with any proceeding to enforce its rights hereunder or under any other Operative
Agreement or any other litigation or proceeding related hereto; provided,
however, the Agent, the Lessor, such Lender or such Holder shall instruct such
independent auditors or other professional advisors to keep such information
confidential in accordance with the terms of this Section 12.13; provided,
further, that in the event of any disclosure of non-public information pursuant
to any of clauses (b), (c), (d), and (f) of this Section 12.13, the Agent, the
Lessor, such Lender or such Holder shall make a good faith attempt, to the
extent practicable, to notify AOR of any such disclosure of non-public
information at least three (3) Business Days prior to disclosing such
information, and in any event shall notify AOR of such disclosure as soon as
practicable.

     12.14.  FINANCIAL REPORTING/TAX CHARACTERIZATION.

     Lessee agrees to obtain advice from its own accountants and tax counsel
regarding the financial reporting treatment and the tax characterization of the
transactions described in the Operative Agreements. Lessee further agrees that
Lessee shall not rely upon any statement of 

                                       59
<PAGE>
 
any Financing Party or any of their
respective Affiliates and/or Subsidiaries regarding any such financial reporting
treatment and/or tax characterization.

     12.15.  SET-OFF.

     In addition to any rights now or hereafter granted under applicable Law and
not by way of limitation of any such rights, upon and after the occurrence of
any Event of Default and during the continuance thereof, each Lender, each
Holder and any assignee of a Lender or a Holder in accordance with the
applicable provisions of the Operative Agreements is hereby authorized by each
Credit Party at any time or from time to time, without notice to any Credit
Party or to any other Person, any such notice being hereby expressly waived to
the extent permitted by applicable law, to set-off and to appropriate and to
apply any and all deposits (general or special, time or demand, including
without limitation indebtedness evidenced by certificates of deposit, whether
matured or unmatured) and any other indebtedness at any time held or owing by
such Lender, such Holder or any such assignee of a Lender or a Holder in
accordance with the applicable provisions of the Operative Agreements to or for
the credit or the account of any Credit Party against and on account of the
obligations of any Credit Party under the Operative Agreements irrespective of
whether or not (a) the Lenders or the Holders shall have made any demand under
any Operative Agreement or (b) the Agent shall have declared any or all of the
obligations of any Credit Party under the Operative Agreements to be due and
payable and although such obligations shall be contingent or unmatured.
 
     12.16  USURY SAVINGS PROVISION.

     NOTWITHSTANDING ANY OTHER PROVISION OF THIS AGREEMENT OR ANY OTHER
OPERATIVE AGREEMENT, IT IS THE INTENT OF THE PARTIES HERETO TO CONFORM TO AND
CONTRACT IN STRICT COMPLIANCE WITH APPLICABLE USURY LAW FROM TIME TO TIME IN
EFFECT.  ANY PAYMENTS HEREUNDER OR UNDER ANY OPERATIVE AGREEMENT CONSTITUTING
INTEREST UNDER ANY APPLICABLE LAW FROM TIME TO TIME IN EFFECT MAY BE REFERRED TO
HEREIN AS "INTEREST."  ALL AGREEMENTS AMONG THE PARTIES HERETO (INCLUDING ALL OF
THE OPERATIVE AGREEMENTS) ARE HEREBY LIMITED BY THE PROVISIONS OF THIS PARAGRAPH
WHICH SHALL OVERRIDE AND CONTROL ALL SUCH AGREEMENTS, WHETHER NOW EXISTING OR
HEREAFTER ARISING AND WHETHER WRITTEN OR ORAL.  IN NO WAY, NOR IN ANY EVENT OR
CONTINGENCY (INCLUDING WITHOUT LIMITATION PREPAYMENT OR ACCELERATION OF THE
MATURITY OF ANY OBLIGATION OR THE EARLY TERMINATION OF THE LEASE FOR ANY
REASON), SHALL ANY INTEREST TAKEN, RESERVED, CONTRACTED FOR, CHARGED, OR
RECEIVED UNDER THIS AGREEMENT OR UNDER ANY OPERATIVE AGREEMENT OR OTHERWISE,
EXCEED THE MAXIMUM NONUSURIOUS AMOUNT PERMISSIBLE UNDER APPLICABLE LAW NOR SHALL
ANY PROVISION CREATE AN OBLIGATION TO PAY UNEARNED INTEREST IN VIOLATION OF
APPLICABLE LAW.  IF, FROM ANY POSSIBLE CONSTRUCTION OF ANY OF THE OPERATIVE
AGREEMENTS OR ANY OTHER DOCUMENT OR AGREEMENT, UNEARNED INTEREST WOULD BE
PAYABLE OR 

                                       60
<PAGE>
 
INTEREST WOULD OTHERWISE BE PAYABLE IN EXCESS OF THE MAXIMUM NONUSURIOUS AMOUNT,
ANY SUCH CONSTRUCTION SHALL BE SUBJECT TO THE PROVISIONS OF THIS PARAGRAPH AND
SUCH AMOUNTS UNDER SUCH DOCUMENTS OR AGREEMENTS SHALL BE AUTOMATICALLY REDUCED
TO THE MAXIMUM NONUSURIOUS AMOUNT PERMITTED UNDER APPLICABLE LAW, WITHOUT THE
NECESSITY OF EXECUTION OF ANY AMENDMENT OR NEW DOCUMENT OR AGREEMENT. IF THE
AGENT, ANY LENDER OR ANY OTHER FINANCING PARTY SHALL EVER RECEIVE ANYTHING OF
VALUE WHICH CONSTITUTES INTEREST UNDER ANY APPLICABLE LAW FROM TIME TO TIME WITH
RESPECT TO THE OBLIGATIONS OWED HEREUNDER OR UNDER ANY OPERATIVE AGREEMENT OR
UNDER APPLICABLE LAW AND WHICH WOULD, APART FROM THIS PROVISION, BE IN EXCESS OF
THE MAXIMUM LAWFUL AMOUNT, AN AMOUNT EQUAL TO THE AMOUNT WHICH WOULD HAVE BEEN
EXCESSIVE INTEREST SHALL, WITHOUT PENALTY, TO THE EXTENT PERMITTED BY APPLICABLE
LAW, BE APPLIED TO THE REDUCTION OF THE COMPONENT OF PAYMENTS DEEMED TO BE
PRINCIPAL AND NOT TO THE PAYMENT OF INTEREST, OR REFUNDED TO THE BORROWER OR ANY
OTHER PAYOR THEREOF, IF AND TO THE EXTENT SUCH AMOUNT WHICH WOULD HAVE BEEN
EXCESSIVE EXCEEDS THE COMPONENT OF PAYMENTS DEEMED TO BE PRINCIPAL. THE RIGHT TO
DEMAND PAYMENT OF ANY AMOUNTS EVIDENCED BY ANY OF THE OPERATIVE AGREEMENTS DOES
NOT INCLUDE THE RIGHT TO RECEIVE ANY INTEREST WHICH HAS NOT OTHERWISE ACCRUED ON
THE DATE OF SUCH DEMAND, AND NEITHER THE AGENT NOR ANY LENDER NOR ANY HOLDER NOR
ANY OTHER FINANCING PARTY INTENDS TO CHARGE OR RECEIVE ANY UNEARNED INTEREST IN
THE EVENT OF SUCH DEMAND. ALL INTEREST PAID OR AGREED TO BE PAID TO THE AGENT OR
ANY LENDER OR ANY HOLDER OR ANY OTHER FINANCING PARTY SHALL, TO THE EXTENT
PERMITTED BY APPLICABLE LAW, BE AMORTIZED, PRORATED, ALLOCATED, AND SPREAD
THROUGHOUT THE FULL TERM (INCLUDING WITHOUT LIMITATION ANY RENEWAL OR EXTENSION)
OF THIS AGREEMENT SO THAT THE AMOUNT OF INTEREST ON ACCOUNT OF SUCH PAYMENTS
DOES NOT EXCEED THE MAXIMUM NONUSURIOUS AMOUNT PERMITTED BY APPLICABLE LAW.
 
     12.17  CHAPTER 346 OF THE TEXAS FINANCE CODE.

     In the event the laws of the State of Texas are applicable to any of the
Operative Agreements or any of the obligations thereunder, to the extent a
higher maximum lawful rate of interest would result from the parties hereto
agreeing that the provisions of Chapter 346 of the Texas Finance Code (relating
to certain revolving credit accounts), as amended, shall not apply to the
Operative Agreements or any of the obligations thereunder, the parties hereto so
agree that the provisions of such Chapter 346 shall not apply.
 
                           [signature pages follow]

                                       61
<PAGE>
 
          IN WITNESS WHEREOF, the parties hereto have caused this Agreement to
be duly executed by their respective officers thereunto duly authorized as of
the day and year first above written.


          AOR SYNTHETIC REAL ESTATE, INC., as the Construction Agent, as the
          Lessee and as a Tranche A Guarantor

          AMERICAN ONCOLOGY RESOURCES, INC.,
          as the Guarantor and as a Tranche A Guarantor

          AOR REAL ESTATE, INC., as a Tranche A Guarantor
          AOR, INC., as a Tranche A Guarantor
          RMCC CANCER CENTER, INC., as a Tranche A Guarantor
          AOR MANAGEMENT COMPANY OF OREGON, INC.,
               as a Tranche A Guarantor
          AOR MANAGEMENT COMPANY OF INDIANA, INC.,
               as a Tranche A Guarantor
          AOR MANAGEMENT COMPANY OF MISSOURI, INC.,
               as a Tranche A Guarantor
          AOR MANAGEMENT COMPANY OF ARIZONA, INC.,
               as a Tranche A Guarantor
          AOR MANAGEMENT COMPANY OF SOUTH CAROLINA, INC., 
               as a Tranche A Guarantor
          AOR MANAGEMENT COMPANY OF OKLAHOMA, INC.,
               as a Tranche A Guarantor
          AOR MANAGEMENT COMPANY OF PENNSYLVANIA, INC., 
               as a Tranche A Guarantor
          AOR MANAGEMENT COMPANY OF VIRGINIA, INC.,
               as a Tranche A Guarantor
          AOR MANAGEMENT COMPANY OF NORTH CAROLINA, INC., 
               as a Tranche A Guarantor
          AOR MANAGEMENT COMPANY OF NEW YORK, INC.,
               as a Tranche A Guarantor
          AOR MANAGEMENT COMPANY OF FLORIDA, INC.
               as a Tranche A Guarantor
          AOR MANAGEMENT COMPANY OF NEVADA, INC.
               as a Tranche A Guarantor
          AOR HOLDING COMPANY OF INDIANA, INC.,
               as a Tranche A Guarantor

                          [SIGNATURE PAGES CONTINUED]
<PAGE>
 
                         AOR MANAGEMENT COMPANY OF TEXAS, INC.
                              as a Tranche A Guarantor
                         AORT HOLDING COMPANY, INC., as a Tranche A Guarantor
                         AORIP, INC., as a Tranche A Guarantor

                         By:____________________________________
                         Name:  L. Fred Pounds
                         Title: Treasurer of each of the foregoing Entities


                         AOR OF TEXAS MANAGEMENT LIMITED PARTNERSHIP,
                         a Texas limited partnership, as a Tranche A Guarantor

                         By:  AOR MANAGEMENT COMPANY OF TEXAS, INC.,
                              a Delaware corporation, as general partner

                         By:____________________________________
                         Name:  L. Fred Pounds
                         Title: Treasurer


                         AOR OF INDIANA MANAGEMENT PARTNERSHIP,
                         an Indiana general partnership, as a Tranche A 
                         Guarantor

                         By: AOR MANAGEMENT COMPANY OF INDIANA, INC., a
                         Delaware corporation, as general partner

                         By:____________________________________
                         Name:  L. Fred Pounds
                         Title: Treasurer


                         By: AOR HOLDING COMPANY OF INDIANA, INC., a 
                         Delaware corporation, as general partner


                         By:____________________________________
                         Name:  L. Fred Pounds
                         Title: Treasurer 



                          [SIGNATURE PAGES CONTINUED]
<PAGE>
 
          FIRST SECURITY BANK, NATIONAL ASSOCIATION,
          not individually, but solely as Owner Trustee under the AOR Trust
          1997-1


          By:_________________________________
          Name:_______________________________
          Title:______________________________



          FIRST UNION NATIONAL BANK, as Agent, as a Lender,
          and as a Holder


          By:_________________________________
          Name:_______________________________
          Title:______________________________



                          [SIGNATURE PAGES CONTINUED]
<PAGE>
 
          THE FIRST NATIONAL BANK OF CHICAGO, as a Lender and 
          as a Holder


          By:_________________________________
          Name:_______________________________
          Title:______________________________



                          [SIGNATURE PAGES CONTINUED]
<PAGE>
 
          ABN AMRO BANK N.V., as a Lender and as a Holder


          By:_________________________________
          Name:_______________________________
          Title:______________________________



          By:_________________________________
          Name:_______________________________
          Title:______________________________



                          [SIGNATURE PAGES CONTINUED]
<PAGE>
 
          TEXAS COMMERCE BANK NATIONAL ASSOCIATION, as a 
          Lender and as a Holder


          By:_________________________________
          Name:_______________________________
          Title:______________________________



                          [SIGNATURE PAGES CONTINUED]
<PAGE>
 
          COOPERATIEVE CENTRALE RAIFFEISEN-
          BOERENLEENBANK B.A., "RABOBANK NEDERLAND",
          NEW YORK BRANCH, as a Lender and as a Holder


          By:_________________________________
          Name:_______________________________
          Title:______________________________

          By:_________________________________
          Name:_______________________________
          Title:______________________________


                          [SIGNATURE PAGES CONTINUED]
<PAGE>
 
          SUNTRUST BANK, TAMPA BAY, as a Lender


          By:_________________________________
          Name:_______________________________
          Title:______________________________



                          [SIGNATURE PAGES CONTINUED]
<PAGE>
 
          THE FUJI BANK, LIMITED, as a Lender


          By:_________________________________
          Name:_______________________________
          Title:______________________________



                          [SIGNATURE PAGES CONTINUED]
<PAGE>
 
          WELLS FARGO BANK (TEXAS) NATIONAL ASSOCIATION, 
          as a Lender


          By:_________________________________
          Name:_______________________________
          Title:______________________________



                          [SIGNATURE PAGES CONTINUED]
<PAGE>
 
          NATIONAL CITY BANK OF KENTUCKY, as a Lender


          By:_________________________________
          Name:_______________________________
          Title:______________________________



                          [SIGNATURE PAGES CONTINUED]
<PAGE>
 
          CREDIT LYONNAIS NEW YORK BRANCH, as a Lender


          By:_________________________________
          Name:_______________________________
          Title:______________________________



                          [SIGNATURE PAGES CONTINUED]
<PAGE>
 
          THE LONG-TERM CREDIT BANK OF JAPAN, LIMITED,
          as a Lender


          By:_________________________________
          Name:_______________________________
          Title:______________________________


                          [SIGNATURE PAGES CONTINUED]
<PAGE>
 
          CORESTATES BANK, N.A., as a Lender


          By:_________________________________
          Name:_______________________________
          Title:______________________________



                          [SIGNATURE PAGES CONTINUED]
<PAGE>
 
          NATIONSBANK OF TEXAS, N.A., as a Lender


          By:_________________________________
          Name:_______________________________
          Title:______________________________
<PAGE>
 
______________________________________________________________________________

                                  Appendix A
                        Rules of Usage and Definitions
______________________________________________________________________________


                              I.  Rules of Usage


The following rules of usage shall apply to this Appendix A and the Operative
Agreements (and each appendix, schedule, exhibit and annex to the foregoing)
unless otherwise required by the context or unless otherwise defined therein:

     (a) Except as otherwise expressly provided, any definitions set forth
herein or in any other document shall be equally applicable to the singular and
plural forms of the terms defined.

     (b) Except as otherwise expressly provided, references in any document to
articles, sections, paragraphs, clauses, annexes, appendices, schedules or
exhibits are references to articles, sections, paragraphs, clauses, annexes,
appendices, schedules or exhibits in or to such document.

     (c) The headings, subheadings and table of contents used in any document
are solely for convenience of reference and shall not constitute a part of any
such document nor shall they affect the meaning, construction or effect of any
provision thereof.

     (d) References to any Person shall include such Person, its successors,
permitted assigns and permitted transferees.

     (e) Except as otherwise expressly provided, reference to any agreement
means such agreement as amended, modified, extended, supplemented, restated
and/or replaced from time to time in accordance with the applicable provisions
thereof.

     (f) Except as otherwise expressly provided, references to any law includes
any amendment or modification to such law and any rules or regulations issued
thereunder or any law enacted in substitution or replacement therefor.

     (g) When used in any document, words such as "hereunder", "hereto",
"hereof" and "herein" and other words of like import shall, unless the context
clearly indicates to the contrary, refer to the whole of the applicable document
and not to any particular article, section, subsection, paragraph or clause
thereof.

     (h) References to "including" means including without limiting the
generality of any description preceding such term and for purposes hereof the
rule of ejusdem generis shall not be applicable to the term "including" or other
similar terms to limit a general statement, followed by 
<PAGE>
 
or referable to an enumeration of specific matters, to matters similar to those
specifically mentioned.

     (i) References herein to "attorney's fees", "legal fees", "costs of
counsel" or other such references shall be deemed to include the allocated cost
of in-house counsel.

     (j) Each of the parties to the Operative Agreements and their counsel have
reviewed and revised, or requested revisions to, the Operative Agreements, and
the usual rule of construction that any ambiguities are to be resolved against
the drafting party shall be inapplicable in the construing and interpretation of
the Operative Agreements and any amendments or exhibits thereto.

     (k) Capitalized terms used in any Operative Agreements which are not
defined in this Appendix A but are defined in another Operative Agreement shall
have the meaning so ascribed to such term in the applicable Operative Agreement.

     (l) If any obligation under the Operative Agreements is required to be
performed on a day that is not a Business Day, such obligation shall be required
to be performed on the next succeeding Business Day (unless otherwise provided
in the Operative Agreements) so long as there shall be no such postponement
beyond the Maturity Date or the Expiration Date.

                               II.  Definitions

     "AAA" shall have the meaning given to such term in Section 12.7(d) of the
Participation Agreement.

     "ABR" shall mean, for any day, a rate per annum equal to the greater of (a)
the Prime Lending Rate in effect on such day, and (b) the Federal Funds
Effective Rate in effect on such day plus one-half of one percent (0.5%). For
purposes hereof: "Prime Lending Rate" shall mean the rate which the Agent
announces from time to time as its prime lending rate as in effect from time to
time. The Prime Lending Rate is a reference rate and does not necessarily
represent the lowest or best rate actually charged to any customer. Any Lender
may make commercial loans or other loans at rates of interest at, above or below
the Prime Lending Rate. The Prime Lending Rate shall change automatically and
without notice from time to time as and when the prime lending rate of the Agent
changes. "Federal Funds Effective Rate" shall mean, for any period, a
fluctuating interest rate per annum equal for each day during such period to the
weighted average of the rates on overnight Federal funds transactions with
members or the Federal Reserve System arranged by Federal funds brokers, as
published for such day (or, if such day is not a Business Day, for the next
preceding Business Day) by the Federal Reserve Bank of New York, or, if such
rate is not so published for any day which is a Business Day, the average of the
quotations for such day on such transactions received by the Agent from three
(3) Federal funds brokers of recognized standing selected by it. Any change in
the ABR due to a change in the Prime Lending Rate or the Federal Funds Effective
Rate shall be effective as of the opening of business on the effective day of
such change in the Prime Lending Rate or the Federal Funds Effective Rate,
respectively.

                                  Appendix A-2
<PAGE>
 
          "ABR Holder Advance" shall mean a Holder Advance bearing a Holder
Yield based on the ABR.

          "ABR Loans" shall mean Loans the rate of interest applicable to which
is based upon the ABR.

          "Acceleration" shall have the meaning given to such term in Section 6
of the Credit Agreement.

          "Accession Agreement" shall mean each Accession Agreement executed
from time to time by Tranche A Guarantors pursuant to Section 5.8 of the
Participation Agreement, in the form attached to the Participation Agreement as
Exhibit K.

          "Accounts" shall have the meaning given to such term in Section 1 of
the Security Agreement.

          "Acquisition Advance" shall have the meaning given to such term in
Section 5.3 of the Participation Agreement.

          "Acquisition Loan" shall mean any Loan made in connection with an
Acquisition Advance.

          "Additional Incorporated Terms" shall have the meaning given to such
term in Section 28.1 of the Lease.

          "Advance" shall mean a Construction Advance or an Acquisition Advance.

          "Affiliate" shall mean, with respect to any Person, any Person or
group acting in concert in respect of the Person in question that, directly or
indirectly, controls or is controlled by or is under common control with such
Person.  For the purpose of this definition, "control" means the possession,
directly or indirectly, of the power to direct or cause the direction of
management and policies, whether through the ownership of voting securities, by
contract or otherwise.

          "After Tax Basis" shall mean, with respect to any payment to be
received, the amount of such payment increased so that, after deduction of the
amount of all taxes required to be paid by the recipient calculated at the then
maximum marginal rates generally applicable to Persons of the same type as the
recipients with respect to the receipt by the recipient of such amounts (less
any tax savings realized as a result of the payment of the indemnified amount),
such increased payment (as so reduced) is equal to the payment otherwise
required to be made.

          "Agency Agreement" shall mean the Agency Agreement, dated on or about
the Initial Closing Date between the Construction Agent and the Lessor.

                                  Appendix A-3
<PAGE>
 
          "Agency Agreement Event of Default" shall mean an "Event of Default"
as defined in Section 5.1 of the Agency Agreement.

          "Agent" shall mean First Union National Bank, as agent for the Lenders
pursuant to the Credit Agreement, or any successor agent appointed in accordance
with the terms of the Credit Agreement and respecting the Security Documents,
for the Lenders and the Holders, to the extent of their interests.

          "Anniversary Date" shall have the meaning given to such term in
Section 2.2 of the Lease.

          "Annualized EBITDA" shall mean, with respect to AOR and its
Subsidiaries, on a consolidated basis, as of the last day of any fiscal quarter,
the product of (a) EBITDA for the fiscal quarter ending on such date, multiplied
by (b) four (4).

          "AOR" shall mean American Oncology Resources, Inc., a Delaware
corporation, and its successors and permitted assigns.

          "AOR Trust 1997-1" shall mean the grantor trust created pursuant to
the terms and conditions of the Trust Agreement.

          "Applicable Margin" shall mean, at any time with respect to any
Eurodollar Loan or any Eurodollar Holder Advances, the applicable percentage
points as determined under the following matrix with reference to the ratio of
Consolidated Debt to Annualized EBITDA calculated as provided below:

<TABLE> 
<CAPTION> 


  Ratio of Consolidated              Applicable Margin for           Applicable Margin for           Applicable Margin for    
Debt to Annualized EBITDA         Eurodollar Tranche A Loans       Eurodollar Tranche B Loans      Eurodollar Holder Advances 
-------------------------         --------------------------       --------------------------      --------------------------
<S>                               <C>                              <C>                             <C> 
Greater than 3.00 to 1.00                 0.875%                            1.250%                          1.635%

Greater than 2.50 to 1.00 but             0.800%                            1.175%                          1.550% 
less than or equal to 3.00 to 
1.00                                      

Greater than 2.00 to 1.00 but             0.550%                            0.925%                          1.300% 
less than or equal to 2.50 to 
1.00                                      

Greater than 1.50 to 1.00 but             0.450%                            0.825%                          1.200% 
less than or equal to 2.00 to 
1.00                                      

Less than or equal to 1.50 to             0.325%                            0.700%                          1.075%
1.00
</TABLE> 

          From the Initial Closing Date until the fifth (5th) day after receipt
by the Agent of the December 31, 1997 financial statements pursuant to Section
28.1 of the Lease, the Applicable 

                                  Appendix A-4
<PAGE>
 
Margin shall be 0.800% (for the Eurodollar Tranche A Loans), 1.175% (for the
Eurodollar Tranche B Loans) and 1.550% (for the Eurodollar Holder Advances). The
Applicable Margin shall be reset from time to time in accordance with the above
matrix on the fifth (5th) day after receipt by the Agent in accordance with
Section 28.1 of the Lease of financial statements together with a Compliance
Certificate (reflecting the computation of the ratio of Consolidated Debt to
Annualized EBITDA as of the last day of the preceding fiscal quarter or fiscal
year, as appropriate).

          "Appraisal" shall mean, with respect to any Property, an appraisal to
be delivered in connection with the Participation Agreement or in accordance
with the terms of the Lease, in each case prepared by a reputable appraiser
reasonably acceptable to the Agent, which in the judgment of counsel to the
Agent, complies with all of the provisions of the Financial Institutions Reform,
Recovery and Enforcement Act of 1989, as amended, the rules and regulations
adopted pursuant thereto, and all other applicable Legal Requirements.

          "Appraisal Procedure" shall have the meaning given such term in
Section 22.4 of the Lease.

          "Approved State" shall mean each of the following: Colorado, Florida,
Indiana, Oklahoma and Texas and any other state within the continental United
States proposed by the Lessee and consented to in writing by the Agent.

          "Appurtenant Rights" shall mean (a) all agreements, easements, rights
of way or use, rights of ingress or egress, privileges, appurtenances,
tenements, hereditaments and other rights and benefits at any time belonging or
pertaining to the Land underlying the Improvements or the Improvements,
including without limitation the use of any streets, ways, alleys, vaults or
strips of land adjoining, abutting, adjacent or contiguous to the Land and (b)
all permits, licenses and rights, whether or not of record, appurtenant to such
Land or the Improvements.

          "Arbitration Rules" shall have the meaning given to such term in
Section 12.7(d) of the Participation Agreement.

          "Assignment and Acceptance" shall mean the Assignment and Acceptance
in the form attached to the Credit Agreement as EXHIBIT B.

          "Available Commitment" shall mean, as to any Lender at any time, an
amount equal to the excess, if any, of (a) the amount of such Lender's
Commitment over (b) the aggregate principal amount of all Loans made by such
Lender as of such date after giving effect to Section 5.2(d) of the
Participation Agreement (but without giving effect to any other repayments or
prepayments of any Loans hereunder).

          "Available Holder Commitments" shall mean an amount equal to the
excess, if any, of (a) the aggregate amount of the Holder Commitments over (b)
the aggregate amount of the Holder Advances made since the Initial Closing Date
after giving effect to Section 5.2(d) of the 

                                  Appendix A-5
<PAGE>
 
Participation Agreement (but without giving effect to any other repayments or
prepayments of any Holder Advances).

          "Bankruptcy Code" shall mean Title 11 of the U. S. Code entitled
"Bankruptcy," as now or hereafter in effect or any successor thereto.

          "Base Amount" shall have the meaning specified in Section 10.1(e) of
the Lease.

          "Basic Rent" shall mean, the sum of (a) the Loan Basic Rent and (b)
the Lessor Basic Rent, calculated as of the applicable date on which Basic Rent
is due.

          "Benefitted Lender" shall have the meaning specified in Section
9.10(a) of the Credit Agreement.

          "Bill of Sale" shall mean a Bill of Sale regarding Equipment in form
and substance satisfactory to the Agent.

          "Board" shall mean the Board of Governors of the Federal Reserve
System of the United States (or any successor).

          "Borrower" shall mean the Owner Trustee, not in its individual
capacity but as Borrower under the Credit Agreement.

          "Borrowing Date" shall mean any Business Day specified in a notice
delivered pursuant to Section 2.3 of the Credit Agreement as a date on which the
Lessor requests the Lenders to make Loans hereunder.

          "Bridge Financing" shall mean the financing provided in favor of the
Owner Trustee by AOR with respect to various properties prior to the Initial
Closing Date.

          "Budgeted Total Property Cost" shall mean, at any date of
determination with respect to any Construction Period Property, an amount equal
to the aggregate amount which the Construction Agent in good faith expects to be
expended in order to achieve Completion with respect to such Property.

          "Business Day" shall mean a day other than a Saturday or Sunday, a
legal holiday or other day on which commercial banks in Charlotte, North
Carolina or, in respect of any determination relevant to an Advance, New York,
New York are required by law to close; provided, however, that when used in
connection with a Eurodollar Loan, the term "Business Day" shall also exclude
any day on which banks are not open for dealings in dollar deposits in the
London interbank market.

          "Capital Lease" shall mean (a) any lease of any property that would,
in accordance with GAAP, be required to be classified and accounted for as a
capital lease on the balance sheet of 

                                  Appendix A-6
<PAGE>
 
the lessee and (b) the Lease and any other tax retention operating lease or
synthetic lease that is treated as a capital lease of the lessee or its
consolidated group for tax purposes.

          "Capital Lease Obligation" shall mean, with respect to any Capital
Lease, the amount of the obligation of the lessee thereunder that would, in
accordance with GAAP, appear on a balance sheet as a liability of such lessee in
respect of such Capital Lease (or such amount similarly calculated for any
Capital Lease that does not appear on a balance sheet), net of any government
grant applicable to such Capital Lease.

          "Capital Stock" shall mean any nonredeemable capital stock of the
Lessee or any of its Subsidiaries, whether common or preferred.

          "Capitalized Lease" shall mean, as applied to any Person, any lease of
property (whether real, personal, tangible, intangible or mixed of such Person)
by such Person as the lessee which would be capitalized on a balance sheet of
such Person prepared in accordance with GAAP.

          "Casualty" shall mean any damage or destruction of all or any portion
of the Property as a result of a fire or other casualty.

          "CERCLA" shall mean the Comprehensive Environmental Response,
Compensation, and Liability Act of 1980, 42 U.S.C. (S) 9601 et seq., as amended
by the Superfund Amendments and Reauthorization Act of 1986.

          "Certificate" shall mean a Certificate in favor of each Holder
regarding the Holder Commitment of such Holder issued pursuant to the terms and
conditions of the Trust Agreement in favor of each Holder.

          "Change of Control" shall mean the occurrence of any one or more of
the following: (i) AOR shall merge or consolidate with or into another
corporation with the effect that the Persons who were the shareholders of AOR
immediately prior to the effective time of such merger or consolidation hold
less than 51% of the combined voting power of the outstanding securities of the
surviving corporation of such merger or the corporation resulting from such
consolidation ordinarily (and apart from rights accruing under special
circumstances) having the right to vote in the election of directors, or (ii)
any Person or "group" (within the meaning of Section 13(d)(3) of the Exchange
Act), other than the Welsh, Carson, Anderson and Stowe group or any of its
affiliates, shall, directly or indirectly, as a result of a tender or exchange
offer, open market purchases, privately negotiated purchases or otherwise, have
become, after the Closing Date, the "beneficial owner" (within the meaning of
Rule 13d-3 under the Exchange Act) of securities of AOR representing 49% or more
of the combined voting power of the then outstanding securities of AOR
ordinarily (and apart from rights accruing under special circumstances) having
the right to vote in the election of directors.

          "Chattel Paper" shall have the meaning given to such term in Section 1
of the Security Agreement.

                                  Appendix A-7
<PAGE>
 
          "Claims" shall mean any and all obligations, liabilities, losses,
actions, suits, penalties, claims, demands, costs and expenses (including
without limitation reasonable attorney's fees and expenses) of any nature
whatsoever.

          "Closing Date" shall mean the Initial Closing Date and each Property
Closing Date.

          "Code" shall mean the Internal Revenue Code of 1986 together with
rules and regulations promulgated thereunder, as amended from time to time, or
any successor statute thereto.

          "Collateral" shall mean all assets of the Lessor, the Construction
Agent and the Lessee, now owned or hereafter acquired, upon which a Lien is
purported to be created by one or more of the Security Documents.

          "Commencement Date" shall have the meaning specified in Section 2.2 of
the Lease.

          "Commitment" shall mean, as to any Lender, the obligation of such
Lender to make the portion of the Loans to the Lessor in an aggregate principal
amount at any time outstanding not to exceed the amount set forth opposite such
Lender's name on Schedule 1.1 of the Credit Agreement, as such amount may be
reduced from time to time in accordance with the provisions of the Credit
Agreement.

          "Commitment Percentage" shall mean, as to any Lender at any time, the
percentage which such Lender's Commitment then constitutes of the aggregate
Commitments (or, at any time after the Commitments shall have expired or
terminated, the percentage which the aggregate principal amount of such Lender's
Loans then outstanding constitutes of the aggregate principal amount of all of
the Loans then outstanding), and such Commitment Percentage shall take into
account both the Lender's Tranche A Commitment and the Lender's Tranche B
Commitment.

          "Commitment Period" shall mean the period from and including the
Initial Closing Date to and including the Construction Period Termination Date,
or such earlier date as the Commitments shall terminate as provided in the
Credit Agreement or the Holder Commitment shall terminate as provided in the
Trust Agreement.

          "Company Obligations" shall mean the obligations of AOR Synthetic Real
Estate, Inc. in any and all capacities, under and with respect to the Operative
Agreements and/or each Property.

          "Completion" shall mean, with respect to a Property, such time as the
acquisition, installation, testing and final completion of the Improvements on
such Property has been achieved in accordance with the Plans and Specifications,
the Agency Agreement and/or the Lease, and in compliance with all Legal
Requirements and Insurance Requirements and a certificate of occupancy has been
issued with respect to such Property by the appropriate governmental entity
(except if non-compliance, individually or in the aggregate, shall not have and
could not reasonably be expected to have a Material Adverse Effect).  If the
Lessor purchases a Property that includes existing Improvements that are to be
immediately occupied by the Lessee, the date of Completion for such Property
shall be the Property Closing Date.

                                  Appendix A-8
<PAGE>
 
          "Completion Date" shall mean, with respect to a Property, the earlier
of (a) the date on which Completion for such Property has occurred or (b) the
Construction Period Termination Date.

          "Compliance Certificate" shall mean a fully completed certificate in
the form of Exhibit N to the Participation Agreement.

          "Condemnation" shall mean any taking or sale of the use, access,
occupancy, easement rights or title to any Property or any part thereof, wholly
or partially (temporarily or permanently), by or on account of any actual or
threatened eminent domain proceeding or other taking of action by any Person
having the power of eminent domain, including without limitation an action by a
Governmental Authority to change the grade of, or widen the streets adjacent to,
any Property or alter the pedestrian or vehicular traffic flow to any Property
so as to result in a change in access to such Property, or by or on account of
an eviction by paramount title or any transfer made in lieu of any such
proceeding or action.

          "Consolidated Debt" shall mean, at any time, the aggregate (without
duplication) of all Debt of AOR and its Subsidiaries as of such date, determined
on a consolidated basis.

          "Consolidated Subsidiary" shall mean, as to any Person, any Subsidiary
of such Person which under the rules of GAAP consistently applied should have
its financial results consolidated with those of such Person for purposes of
financial accounting statements.

          "Construction Advance" shall mean an advance of funds to pay Property
Costs pursuant to Section 5.4 of the Participation Agreement.

          "Construction Agent" shall mean AOR Synthetic Real Estate, Inc., a
Delaware corporation, as the construction agent under the Agency Agreement.

          "Construction Budget" shall mean the cost of acquisition,
installation, testing, constructing and developing any Property as determined by
the Construction Agent in its reasonable, good faith judgment.

          "Construction Commencement Date" shall mean, with respect to
Improvements, the date on which construction of such Improvements commences
pursuant to the Agency Agreement.

          "Construction Contract" shall mean any contract entered into between
the Construction Agent or the Lessee with a Contractor for the construction of
Improvements or any portion thereof on the Property.

          "Construction Loan" shall mean any Loan made in connection with a
Construction Advance.

                                  Appendix A-9
<PAGE>
 
          "Construction Loan Property Cost" shall mean with respect to each
Construction Period Property at the date of determination, an amount equal to
(a) the aggregate principal amount of Construction Loans made on or prior to
such date with respect to the Property minus (b) the aggregate principal amount
of prepayments or repayments of the Loans allocated to reduce the Construction
Loan Property Cost of such Property pursuant to Section 2.6(c) of the Credit
Agreement.

          "Construction Period" shall mean, with respect to a Property, the
period commencing on the Construction Commencement Date for such Property and
ending on the Completion Date for such Property.

          "Construction Period Property" means, at any date of determination,
any Property as to which the Rent Commencement Date has not occurred on or prior
to such date.

          "Construction Period Termination Date" shall mean (a) the earlier of
(i) the date that the Commitments have been terminated in their entirety in
accordance with the terms of Section 2.5(a) of the Credit Agreement, or (ii) the
second anniversary of the Initial Closing Date or (b) such later date as shall
be agreed to by the Majority Secured Parties.

          "Contingent Obligation" shall mean, with respect to any Person, any
direct or indirect liability of such Person with respect to any Debt, lease,
dividend, guaranty, letter of credit or other obligation (the "primary
obligation") of another Person (the "primary obligor"), whether or not
contingent, (a) to purchase, repurchase or otherwise acquire such primary
obligations or any property constituting direct or indirect security therefor,
(b) to advance or provide funds (i) for the payment or discharge of any such
primary obligation or (ii) to maintain working capital or equity capital of the
primary obligor or otherwise to maintain the net worth or solvency or any
balance sheet item, level of income or financial condition of the primary
obligor, (c) to purchase property, securities or services primarily for the
purpose of assuring the owner of any such primary obligation of the ability of
the primary obligor in respect thereof to make payment of such primary
obligation or (d) otherwise to assure or hold harmless the owner of any such
primary obligation against loss or failure or inability to perform in respect
thereof.   The amount of any Contingent Obligation shall be deemed to be an
amount equal to the stated or determinable amount of the primary obligation in
respect of which such Contingent Obligation is made or, if not stated or
determinable, the maximum reasonably anticipated liability in respect thereof as
determined by such Person in good faith

          "Contractor" shall mean each entity with whom the Construction Agent
or the Lessee contracts to construct any Improvements or any portion thereof on
the Property.

          "Controlled Group" shall mean all members of a controlled group of
corporations and all trades or businesses (whether or not incorporated) under
common control which, together with AOR, are treated as a single employer under
Section 414 of the Code.

          "Co-Owner Trustee" shall have the meaning specified in Section 9.2 of
the Trust Agreement.

                                 Appendix A-10
<PAGE>
 
          "Covenant Compliance Worksheet" shall mean a fully completed
certificate in the form of Attachment A to EXHIBIT L to the Participation
Agreement.

          "Credit Agreement" shall mean the Credit Agreement, dated on or about
the Initial Closing Date, among the Lessor, the Agent, the Lenders, as specified
therein, AOR and the other Tranche A Guarantors.

          "Credit Agreement Default" shall mean any event or condition which,
with the lapse of time or the giving of notice, or both, would constitute a
Credit Agreement Event of Default.

          "Credit Agreement Event of Default" shall mean any event or condition
defined as an "Event of Default" in Section 6 of the Credit Agreement.

          "Credit Documents" shall mean the Participation Agreement, the Credit
Agreement, the Notes and the Security Documents.

          "Credit Parties" shall mean, collectively, the Construction Agent, the
Lessee, the Guarantor and each Tranche A Guarantor.

          "Debt" shall mean, with respect to any Person, without duplication,
(a) all indebtedness of such Person for money borrowed, (b) all reimbursement
obligations of such Person with respect to surety bonds, letters of credit and
bankers' acceptances (in each case, whether or not matured), (c) all obligations
of such Person evidenced by notes, bonds, debentures or similar instruments, (d)
all obligations of such Person to pay the deferred purchase price of property or
services (including seller subordinated notes, contingent or otherwise), other
than trade payables, (e) all indebtedness created or arising under any
conditional sale or other title retention agreement with respect to property
acquired by such Person (even though the rights and remedies of the seller or
lender under such agreement in the event of default are limited to repossession
or sale of such property), (f) all Capital Lease Obligations of such Person, (g)
all obligations of such Person to purchase, redeem, retire, defease or otherwise
make any payment in respect of any capital stock or other equity securities
that, by their stated terms (or by the terms of any equity securities issuable
upon conversion thereof or in exchange therefor), or upon the occurrence of any
event, mature or are mandatorily redeemable, or are redeemable at the option of
the holder thereof, in whole or in part, (h) all indebtedness referred to in
clauses (a) through (g) above to the extent secured by any lien on any property
or asset owned or held by such Person regardless of whether the indebtedness
secured thereby shall have been assumed by such Person or is nonrecourse to the
credit of such Person and (i) any Contingent Obligation of such Person.

          "Deed" shall mean a warranty deed regarding the Land and/or
Improvements in form and substance reasonably satisfactory to the Agent.

          "Default" shall mean any event, act or condition which with notice or
lapse of time, or both, would constitute an Event of Default.

                                 Appendix A-11
<PAGE>
 
          "Defaulting Holder" shall have the meaning given to such term in
Section 12.4 of the Participation Agreement.

          "Defaulting Lender" shall have the meaning given to such term in
Section 12.4 of the Participation Agreement.

          "Deficiency Balance" shall have the meaning given in Section 22.1(b)
of the Lease Agreement.

          "Disputes" shall have the meaning given to such term in Section
12.7(d) of the Participation Agreement.

          "Documents" shall have the meaning given to such term in Section 1 of
the Security Agreement.

          "Dollars" and "$" shall mean dollars in lawful currency of the United
States of America.

          "EBITDA" shall mean, for any period, an amount equal to, without
duplication, the sum of (a) net income (determined in accordance with GAAP)
earned in such period, plus (b) to the extent net income has been reduced
thereby, the sum of (i) depreciation and amortization expense, plus (ii)
Interest Expense, plus (iii) federal and state income taxes.

          "Effective Date" shall mean December 31, 1997.

          "Election Date" shall have the meaning given to such term in Section
20.1 of the Lease.

          "Election Notice" shall have the meaning given to such term in Section
20.1 of the Lease.

          "Eligible Assignee" shall mean (i) a commercial bank organized under
the laws of the United States or any state thereof and having total assets in
excess of $5,000,000,000, (ii) a commercial bank organized under the laws of any
other country that is a member of the OECD or a political subdivision of any
such country and having total assets in excess of 5,000,000,000, provided, that
such bank is acting through a branch or agency located in the United States, in
the country under the laws of which it is organized or in another country that
is also a member of the OECD, (iii) the central bank of any country that is a
member of the OECD, (iv) a finance company, mutual fund, insurance company or
other financial institution that is engaged in making, purchasing or otherwise
investing in commercial loans in the ordinary course of its business and having
total assets in excess of $500,000,000, (v) any Affiliate of an existing Lender
or (vi) any other Person (other than an Affiliate of AOR) approved by the Agent
and AOR, which approval shall not be unreasonably withheld; provided, however,
that in no event shall the withholding of approval by AOR under this definition
be considered unreasonable if (i) AOR has had prior dealings with such Person
which AOR regards as unfavorable or (ii) such Person provides banking or other
financial services to any of AOR's competitors.

                                 Appendix A-12
<PAGE>
 
          "Employee Benefit Plan" or "Plan" shall mean an employee benefit plan
(within the meaning of Section 3(3) of ERISA, including without limitation any
Multiemployer Plan), or any "plan" as defined in Section 4975(e)(1) of the Code
and as interpreted by the Internal Revenue Service and the Department of Labor
in rules, regulations, releases or bulletins in effect on any Closing Date.

          "Environmental Claims" shall mean any investigation, notice,
violation, demand, allegation, action, suit, injunction, judgment, order,
consent decree, penalty, fine, lien, proceeding, or claim (whether
administrative, judicial, or private in nature) arising (a) pursuant to, or in
connection with, an actual or alleged violation of, any Environmental Law, (b)
in connection with any Hazardous Substance, (c) from any abatement, removal,
remedial, corrective, or other response action in connection with a Hazardous
Substance, Environmental Law, or other order of a Tribunal or (d) from any
actual or alleged damage, injury, threat, or harm to health, safety, natural
resources, or the environment.

          "Environmental Laws" shall mean any Law, permit, consent, approval,
license, award, or other authorization or requirement of any Tribunal relating
to emissions, discharges, releases, threatened releases of any Hazardous
Substance into ambient air, surface water, ground water, publicly owned
treatment works, septic system, or land, or otherwise relating to the handling,
storage, treatment, generation, use, or disposal of Hazardous Substances,
pollution or to the protection of health or the environment, including without
limitation CERCLA, the Resource Conservation and Recovery Act, 42 U.S.C. (S)
6901, et seq., and state statutes analogous thereto.

          "Environmental Violation" shall mean any activity, occurrence or
condition that violates or threatens (if the threat then requires remediation
under any Environmental Law and is not remediated during any grace period
allowed under such Environmental Law) to violate or results in or threatens (if
the threat then requires remediation under any Environmental Law and is not
remediated during any grace period allowed under such Environmental Law) to
result in noncompliance with any Environmental Law.

          "Equipment" shall mean equipment, apparatus, furnishings, fittings and
personal property of every kind and nature whatsoever purchased, leased or
otherwise acquired using the proceeds of the Loans or the Holder Advances by the
Construction Agent, the Lessee or the Lessor and all improvements and
modifications thereto and replacements thereof, whether or not now owned or
hereafter acquired or now or subsequently attached to, contained in or used or
usable in any way in connection with any operation of any Improvements or other
improvements to real property, including but without limiting the generality of
the foregoing, all equipment described in the Appraisal including without
limitation all heating, electrical, and mechanical equipment, lighting,
switchboards, plumbing, ventilation, air conditioning and air-cooling apparatus,
refrigerating, and incinerating equipment, escalators, elevators, loading and
unloading equipment and systems, cleaning systems (including without limitation
window cleaning apparatus), telephones, communication systems (including without
limitation satellite dishes and antennae), televisions, computers, sprinkler
systems and other fire prevention and extinguishing apparatus and materials,
security systems, motors, engines, machinery, pipes, pumps, tanks, conduits,
appliances, fittings and fixtures of every kind and description.

                                 Appendix A-13
<PAGE>
 
          "Equipment Schedule" shall mean (a) each Equipment Schedule attached
to the applicable Requisition and (b) each Equipment Schedule attached to the
applicable Lease Supplement.

          "ERISA" shall mean the Employee Retirement Income Security Act of
1974, as amended.

          "ERISA Affiliate" shall mean each entity required to be aggregated
with any Credit Party pursuant to the requirements of Section 414(b) or (c) of
the Code.

          "Eurocurrency Reserve Requirements" shall mean for any day as applied
to a Eurodollar Loan, the aggregate (without duplication) of the maximum rates
(expressed as a decimal) of reserve requirements in effect on such day
(including without limitation basic, supplemental, marginal and emergency
reserves under any regulations of the Board or other Governmental Authority
having jurisdiction with respect thereto) dealing with reserve requirements
prescribed on eurocurrency funding (currently referred to as "Eurocurrency
liabilities" in Regulation D) maintained by a member bank of the Federal Reserve
System.

          "Eurodollar Holder Advance" shall mean a Holder Advance bearing a
Holder Yield based on the Eurodollar Rate.

          "Eurodollar Loans" shall mean Loans the rate of interest applicable to
which is based upon the Eurodollar Rate.

          "Eurodollar Rate" shall mean for the Interest Period for each
Eurodollar Loan or Eurodollar Holder Advance comprising part of the same
borrowing or advance (including without limitation conversions, extensions and
renewals), a per annum interest rate equal to the per annum rate determined by
the Agent on the basis of the offered rates for deposits in dollars for a period
of time corresponding to such Interest Period (and commencing on the first day
of such Interest Period), which appear on the Reuters Screen LIBO Page as of
11:00 a.m. (London time) two (2) Business Days before the first day of such
Interest Period (provided, that if at least two (2) such offered rates appear on
the Reuters Screen LIBO Page, the rate in respect of such Interest Period will
be the arithmetic mean of such offered rates).  As used herein, "Reuters Screen
LIBO Page" means the display designated as page "LIBO" on the Reuters Monitor
Money Rates Service (or such other page as may replace the LIBO page on that
service for the purpose of displaying London interbank offered rates of major
banks) ("RMMRS").  In the event the RMMRS is not then quoting such offered
rates, "Eurodollar Rate" shall mean for the Interest Period for each Eurodollar
Loan or Eurodollar Holder Advance comprising part of the same borrowing or
advance (including without limitation conversions, extensions and renewals), the
average (rounded upward to the nearest one-hundredth (1/100) of one percent
(1%)) per annum rate of interest determined by the office of the Agent (each
such determination to be presumptively correct) as of two (2) Business Days
prior to the first day of such Interest Period, as the effective rate at which
deposits in immediately available funds in U.S. dollars are being, have been, or
would be offered or quoted by the Agent to major banks in the applicable
interbank 

                                 Appendix A-14
<PAGE>
 
market for Eurodollar deposits at any time during the Business Day which is the
second Business Day immediately preceding the first day of such Interest Period,
for a term comparable to such Interest Period and in the amount of the requested
Eurodollar Loan and/or Eurodollar Holder Advance. If no such offers or quotes
are generally available for such amount, then the Agent shall be entitled to
determine the Eurodollar Rate by estimating in its reasonable judgment the per
annum rate (as described above) that would be applicable if such quote or offers
were generally available.

          "Event of Default" shall mean a Lease Event of Default, an Agency
Agreement Event of Default or a Credit Agreement Event of Default.

          "Excepted Payments" shall mean: (a) all indemnity payments (including
without limitation indemnity payments made pursuant to Section 11 of the
Participation Agreement), whether made by adjustment to Basic Rent or otherwise,
to which the Owner Trustee, any Holder or any of their respective Affiliates,
agents, officers, directors or employees is entitled;

          (b) any amounts (other than Basic Rent or Termination Value) payable
under any Operative Agreement to reimburse the Owner Trustee, any Holder or any
of their respective Affiliates (including without limitation the reasonable
expenses of the Owner Trustee, the Trust Company and the Holders incurred in
connection with any such payment) for performing or complying with any of the
obligations of any Credit Party under and as permitted by any Operative
Agreement;

          (c) any amount payable to a Holder by any transferee of such interest
of a Holder as the purchase price of such Holder's interest in the Trust Estate
(or a portion thereof);

          (d) any insurance proceeds (or payments with respect to risks self-
insured or policy deductibles) under liability policies other than such proceeds
or payments payable to the Agent or any Lender;

          (e) any insurance proceeds under policies maintained by the Owner
Trustee or any Holder;

          (f) Transaction Expenses or other amounts, fees, disbursements or
expenses paid or payable to or for the benefit of the Owner Trustee or any
Holder under any Operative Agreement;

          (g) all right, title and interest of any Holder or the Owner Trustee
to any Property or any portion thereof or any other property to the extent any
of the foregoing has been released from the Liens of the Security Documents and
the Lease pursuant to the terms thereof;

          (h) upon termination of the Credit Agreement pursuant to the terms
thereof, all remaining property covered by the Lease or Security Documents
unless such is payable to another Person pursuant to an express provision of any
Operative Agreement;

          (i) all payments in respect of the Holder Yield;

                                 Appendix A-15
<PAGE>
 
          (j) any payments in respect of interest to the extent attributable to
payments referred to in clauses (a) through (i) above; and

          (k) any rights of either the Owner Trustee or the Trust Company to
demand, collect, sue for or otherwise receive and enforce payment of any of the
foregoing amounts, provided, that such rights shall not include the right to
terminate the Lease.

          "Excess Proceeds" shall mean the excess, if any, of the aggregate of
all awards, compensation or insurance proceeds payable in connection with a
Casualty or Condemnation over the Termination Value paid by the Lessee pursuant
to the Lease with respect to such Casualty or Condemnation.

          "Exculpated Persons" shall mean the Borrower, the Holders, the Lessor,
their officers, directors, shareholders and partners.

          "Exempt Payments" shall have the meaning specified in Section 11.2(e)
of the Participation Agreement.

          "Expiration Date" shall mean the last day of the Term; provided, in no
event shall the Expiration Date be later than the fifth annual anniversary of
the Initial Closing Date, unless such later date has been expressly agreed to in
writing by each of the Lessor, the Lessee, the Agent, the Lenders and the
Holders.

          "Extension Option" shall mean the meaning given to such term in
Section 20.1 of the Lease.

          "Facility Fee" shall mean, collectively, the Holder Facility Fee and
the Lender Facility Fee.

          "Fair Market Sales Value" shall mean, with respect to any Property,
the amount, which in any event, shall not be less than zero (0), that would be
paid in cash in an arms-length transaction between an informed and willing
purchaser and an informed and willing seller, neither of whom is under any
compulsion to purchase or sell, respectively, such Property.  Fair Market Sales
Value of any Property shall be determined based on the assumption that, except
for purposes of Section 17 of the Lease, such Property is in the condition and
state of repair required under Section 10.1 of the Lease and each Credit Party
is in compliance with the other requirements of the Operative Agreements.

          "Federal Funds Effective Rate" shall have the meaning given to such
term in the definition of ABR.

          "Financing Party" shall mean the Lessor, the Owner Trustee, in its
trust capacity, the Agent, the Holders, the Lenders.

                                 Appendix A-16
<PAGE>
 
          "Fixtures" shall mean all fixtures relating to the Improvements,
including without limitation all components thereof, located in or on the
Improvements, together with all replacements, modifications, alterations and
additions thereto.

          "Force Majeure Event" shall mean any event beyond the control of the
Construction Agent, other than a Casualty or Condemnation, including without
limitation strikes, lockouts, adverse soil conditions, acts of God, adverse
weather conditions, inability to obtain labor or materials, governmental
activities, civil commotion and enemy action; but excluding any event, cause or
condition that results from the Construction Agent's financial condition.

          "Form 1001" shall have the meaning specified in Section 11.2(e) of the
Participation Agreement.

          "Form 4224" shall have the meaning specified in Section 11.2(e) of the
Participation Agreement.

          "GAAP" shall mean generally accepted accounting principles set forth
in the opinions and pronouncements of the accounting principles board of the
American Institute of Certified Public Accountants, and statements and
pronouncements of the Financial Accounting Standards Board or in such other
statements by such other entity as may be approved by a significant segment of
the accounting profession, that are applicable to the circumstances as of the
date of determination.

          "Governmental Action" shall mean all permits, authorizations,
registrations, consents, approvals, waivers, exceptions, variances, orders,
judgments, written interpretations, decrees, licenses, exemptions, publications,
filings, notices to and declarations of or with, or required by, any
Governmental Authority, or required by any Legal Requirement, and shall include,
without limitation, all environmental and operating permits and licenses that
are required for the full use, occupancy, zoning and operating of the Property.

          "Governmental Authority" shall mean any nation or government, any
state or other political subdivision thereof and any entity exercising
executive, legislative, judicial, regulatory or administrative functions of or
pertaining to government.

          "Ground Lease" shall mean a ground lease respecting any Property which
is in form and substance reasonably satisfactory to the Agent.

          "Guarantor" shall mean AOR.

          "Hard Costs" shall mean all costs and expenses payable for supplies,
materials, labor and profit with respect to the Improvements under any
Construction Contract.

          "Hazardous Substance" shall mean any of the following:  (a) any
petroleum or petroleum product, explosives, radioactive materials, asbestos,
formaldehyde, polychlorinated biphenyls, lead and radon gas to the extent any of
the foregoing are harmful or hazardous to the 

                                 Appendix A-17
<PAGE>
 
environment or human health or safety as determined in accordance with any
Environmental Law or otherwise constitute an Environmental Violation; (b) any
substance, material, product, derivative, compound or mixture, mineral,
chemical, waste, gas, medical waste, or pollutant, in each case whether
naturally occurring, man-made or the by-product of any process, that is toxic,
harmful or hazardous to the environment or human health or safety as determined
in accordance with any Environmental Law; or (c) any substance, material,
product, derivative, compound or mixture, mineral, chemical, waste, gas, medical
waste or pollutant that would support the assertion of any claim under any
Environmental Law, whether or not defined as hazardous as such under any
Environmental Law.

          "Holder Advance" shall mean any advance made by any Holder to the
Owner Trustee pursuant to the terms of the Trust Agreement or the Participation
Agreement.

          "Holder Amount" shall mean as of any date, the aggregate amount of
Holder Advances made by each Holder to the Trust Estate pursuant to Section 2 of
the Participation Agreement and Section 3.1 of the Trust Agreement less any
payments of any Holder Advances received by the Holders pursuant to Section 3.4
of the Trust Agreement.

          "Holder Commitments" shall mean $2,250,000; provided, if there shall
be more than one (1) Holder, the Holder Commitment of each Holder shall be as
set forth in Schedule I to the Trust Agreement as such Schedule I may be amended
and replaced from time to time, as such amount may be increased or reduced from
time to time in accordance with the provisions of the Operative Agreements.

          "Holder Construction Property Cost" shall mean, with respect to each
Construction Period Property, at any date of determination, an amount equal to
the outstanding Holder Advances made with respect thereto under the Trust
Agreement.

          "Holder Facility Fee" shall have the meaning given to such term in
Section 7.4 of the Participation Agreement.

          "Holder Overdue Rate" shall mean the lesser of (a) the then current
rate of Holder Yield respecting the particular amount in question plus two
percent (2%) and (b) the highest rate permitted by applicable law.

          "Holder Property Cost" shall mean with respect to a Property an amount
equal to the outstanding Holder Advances with respect thereto.

          "Holder Yield" shall mean with respect to Holder Advances from time to
time either the Eurodollar Rate plus the Applicable Margin or the ABR as elected
by the Owner Trustee from time to time with respect to such Holder Advances in
accordance with the terms of the Trust Agreement; provided, however, (a) upon
delivery of the notice described in Section 3.7(c) of the Trust Agreement, the
outstanding Holder Advances of each Holder shall bear a yield at the ABR
applicable from time to time from and after the dates and during the periods
specified in Section 3.7(c) of the Trust Agreement, and (b) upon the delivery by
a Holder of the notice described in 

                                 Appendix A-18
<PAGE>
 
Section 11.3(f) of the Participation Agreement, the Holder Advances of such
Holder shall bear a yield at the ABR applicable from time to time after the
dates and during the periods specified in Section 11.3(f) of the Participation
Agreement.

          "Holders" shall mean First Union National Bank and shall include the
other banks and financial institutions which may be from time to time holders of
Certificates in connection with the AOR Trust 1997-1.

          "Impositions" shall mean, except to the extent described in the
following sentence, any and all liabilities, losses, expenses, costs, charges
and Liens of any kind whatsoever for fees, taxes, levies, imposts, duties,
charges, assessments or withholdings ("Taxes") including but not limited to (i)
real and personal property taxes, including without limitation personal property
taxes on any property covered by the Lease that is classified by Governmental
Authorities as personal property, and real estate or ad valorem taxes in the
nature of property taxes; (ii) sales taxes, use taxes and other similar taxes
(including rent taxes and intangibles taxes); (iii) excise taxes; (iv) real
estate transfer taxes, conveyance taxes, stamp taxes and documentary recording
taxes and fees; (v) taxes that are or are in the nature of franchise, income,
value added, privilege and doing business taxes, license and registration fees;
(vi) assessments on any Property, including without limitation all assessments
for public Improvements or benefits, whether or not such improvements are
commenced or completed within the Term; and (vii) taxes, Liens, assessments or
charges asserted, imposed or assessed against the Lessee or any of its
Affiliates by the PBGC or any governmental authority succeeding to or performing
functions similar to, the PBGC; and in each case all interest, additions to tax
and penalties thereon, which at any time prior to, during or with respect to the
Term or in respect of any period for which the Lessee shall be obligated to pay
Supplemental Rent, may be levied, assessed or imposed by any Governmental
Authority upon or with respect to (a) any Property or any part thereof or
interest therein; (b) the leasing, financing, refinancing, demolition,
construction, substitution, subleasing, assignment, control, condition,
occupancy, servicing, maintenance, repair, ownership, possession, activity
conducted on, delivery, insuring, use, operation, improvement, sale, transfer of
title, return or other disposition of such Property or any part thereof or
interest therein; (c) the Notes, other indebtedness with respect to any
Property, or the Certificates, or any part thereof or interest therein; (d) the
rentals, receipts or earnings arising from any Property or any part thereof or
interest therein; (e) the Operative Agreements, the performance thereof, or any
payment made or accrued pursuant thereto; (f) the income or other proceeds
received with respect to any Property or any part thereof or interest therein
upon the sale or disposition thereof; (g) any contract (including the Agency
Agreement) relating to the construction, acquisition or delivery of the
Improvements or any part thereof or interest therein; (h) the issuance of the
Notes or the Certificates; (i) the Owner Trustee, the Trust or the Trust Estate;
or (j) otherwise in connection with the transactions contemplated by the
Operative Agreements.

          "Improvements" shall mean, with respect to the construction,
renovations and/or Modifications on any Land, all buildings, structures,
Fixtures, and other improvements of every kind existing at any time and from
time to time on or under the Land purchased, leased or otherwise acquired using
the proceeds of the Loans or the Holder Advances, together with any and all
appurtenances to such buildings, structures or improvements, including without
limitation 

                                 Appendix A-19
<PAGE>
 
sidewalks, utility pipes, conduits and lines, parking areas and roadways, and
including without limitation all Modifications and other additions to or changes
in the Improvements at any time, including without limitation (a) any
Improvements existing as of the Property Closing Date as such Improvements may
be referenced on the applicable Requisition and (b) any Improvements made
subsequent to such Property Closing Date.

          "Incorporated Covenants" shall have the meaning given to such term in
Section 28.1 of the Lease.

          "Incorporated Representations and Warranties" shall have the meaning
given to such term in Section 28.1 of the Lease.

          "Indebtedness" of a Person shall mean, without duplication, such
Person's:

          (a) obligations for borrowed money;

          (b) obligations representing the deferred purchase price of Property
     (whether real, personal, tangible, intangible or mixed) or services (other
     than accounts payable arising in the ordinary course of such Person's
     business );

          (c) obligations, whether or not assumed, secured by liens or payable
     out of the proceeds or production from property now or hereafter owned or
     acquired by such Person;

          (d) obligations which are evidenced by notes, acceptances or other
     instruments;

          (e)  Capital Lease Obligations;

          (f) net liabilities under Interest Rate Protection Agreements; and

          (g) contingent obligations, to the extent such guarantee, affirm or
     otherwise are in support of the types of obligations referenced in the
     preceding sections (a) through (f).

          "Indemnified Person" shall mean the Lessor, the Owner Trustee, in its
individual and its trust capacity, the Trust, the Trust Company, the Agent, the
Holders, the Lenders and their respective successors, assigns, directors,
shareholders, partners, officers, employees, agents and Affiliates.

          "Indemnity Provider" shall mean, respecting each Property, the Lessee.

          "Initial Closing Date" shall mean December 31, 1997 .

                                 Appendix A-20
<PAGE>
 
          "Initial Construction Advance" shall mean any initial Advance to pay
for:  (a) Property Costs for construction of any Improvements; and (b) the
Property Costs of restoring or repairing any Property which is required to be
restored or repaired in accordance with Section 15.1(e) of the Lease.

          "Instruments" shall have the meaning given to such term in Section 1
of the Security Agreement.

          "Insurance Requirements" shall mean all terms and conditions of any
insurance policy either required by the Lease to be maintained by the Lessee or
required by the Agency Agreement to be maintained by the Construction Agent, and
all requirements of the issuer of any such policy and, regarding self insurance,
any other requirements of the Lessee.

          "Interest Expense" shall mean, for any period, total interest expense
of AOR and its Subsidiaries on a consolidated basis for such period (including
without limitation capitalized interest expense and interest expense
attributable to Capital Lease Obligations), determined in accordance with GAAP.

          "Interest Period" shall mean (a) during the Commitment Period and
thereafter as to any Eurodollar Loan or Eurodollar Holder Advance (i) with
respect to the initial Interest Period, the period beginning on the date of the
first Eurodollar Loan and Eurodollar Holder Advance and ending one (1) month,
two (2) months, three (3) months or (subject to availability for all Lenders and
Holders) six (6) months thereafter, as selected by the Lessor (in the case of a
Eurodollar Loan) or the Owner Trustee (in the case of a Eurodollar Holder
Advance) in its applicable notice given with respect thereto and (ii)
thereafter, each period commencing on the last day of the next preceding
Interest Period applicable to such Eurodollar Loan or Eurodollar Holder Advance
and ending one (1) month, two (2) months or three (3) months thereafter, as
selected by the Lessor by irrevocable notice to the Agent (in the case of a
Eurodollar Loan) or by the Owner Trustee (in the case of a Eurodollar Holder
Advance) in each case not less than three (3) Business Days prior to the last
day of the then current Interest Period with respect thereto; provided, however,
that all of the foregoing provisions relating to Interest Periods are subject to
the following: (A) if any Interest Period would end on a day which is not a
Business Day, such Interest Period shall be extended to the next succeeding
Business Day (except that where the next succeeding Business Day falls in the
next succeeding calendar month, then on the next preceding Business Day), (B) no
Interest Period shall extend beyond the Maturity Date or the Expiration Date, as
the case may be, (C) where an Interest Period begins on a day for which there is
no numerically corresponding day in the calendar month in which the Interest
Period is to end, such Interest Period shall end on the last Business Day of
such calendar month, (D) there shall not be more than four (4) Interest Periods
outstanding at any one (1) time.

          "Interest Rate Protection Agreements" shall mean all interest rate
swap agreements, interest rate cap agreements, interest rate collar agreements,
interest rate insurance or other hedging arrangements and all other similar
agreements or arrangements designed to protect against fluctuations in interest
rates.

                                 Appendix A-21
<PAGE>
 
          "Investment Company Act" shall mean the Investment Company Act of
1940, as amended, together with the rules and regulations promulgated
thereunder.

          "Land" shall mean a parcel of real property described on (a) the
Requisition issued by the Construction Agent on the Property Closing Date
relating to such parcel and (b) the schedules to each applicable Lease
Supplement executed and delivered in accordance with the requirements of Section
2.4 of the Lease.

          "Law" shall mean any statute, law, ordinance, regulation, rule,
directive, order, writ, injunction or decree of any Tribunal.

          "Lease" or "Lease Agreement" shall mean the Lease Agreement dated on
or about the Initial Closing Date, between the Lessor and the Lessee, together
with any Lease Supplements thereto.

          "Lease Default" shall mean any event or condition which, with the
lapse of time or the giving of notice, or both, would constitute a Lease Event
of Default.

          "Lease Event of Default" shall have the meaning specified in Section
17.1 of the Lease.

          "Lease Supplement" shall mean each Lease Supplement substantially in
the form of EXHIBIT A to the Lease, together with all attachments and schedules
thereto.

          "Legal Requirements" shall mean all foreign, federal, state, county,
municipal and other governmental statutes, laws, rules, orders, regulations,
ordinances, judgments, decrees and injunctions applicable to the Owner Trustee,
any Holder, the Lessor, the Lessee, the Agent, any Lender or any Property, Land,
Improvement, Equipment or the taxation, demolition, construction, use or
alteration of such Improvements, whether now or hereafter enacted and in force,
including without limitation any that require repairs, modifications or
alterations in or to any Property or in any way limit the use and enjoyment
thereof (including without limitation all building, zoning and fire codes and
the Americans with Disabilities Act of 1990, 42 U.S.C. (S) 12101 et. seq., and
any other similar federal, state or local laws or ordinances and the regulations
promulgated thereunder) and any that may relate to environmental requirements
(including without limitation all Environmental Laws), and (to the extent
required by Law) all permits, certificates of occupancy, licenses, authoriza
tions and regulations relating thereto, and all covenants, agreements,
restrictions and encumbrances contained in any instruments which are either of
record or known to the Lessee affecting any Property or the Appurtenant Rights.

          "Lender Commitments" shall mean $72,750,000; provided, if there shall
be more than one (1) Lender, the Lender Commitment of each Lender shall be as
set forth in Schedule 1.1 to the Credit Agreement as such Schedule 1.1 may be
amended and replaced from time to time, as such amount may be increased or
reduced from time to time in accordance with the provisions of the Operative
Agreements.

                                 Appendix A-22
<PAGE>
 
          "Lender Facility Fee" shall have the meaning given to such term in
Section 7.4 of the Participation Agreement.

          "Lender Financing Statements" shall mean UCC financing statements and
fixture filings appropriately completed and executed for filing in the
applicable jurisdiction in order to procure a security interest in favor of the
Agent in the Collateral subject to the Security Documents.

          "Lenders" shall mean First Union National Bank and shall include the
other banks and financial institutions which may be from time to time party to
the Participation Agreement and the Credit Agreement.

          "Lessee" shall have the meaning set forth in the Lease.

          "Lessee Assets" shall mean all right, title and interest of Lessee in
and to any and all real and personal properties and fixtures, of every kind and
description, tangible or intangible, whether now owned or hereafter existing or
acquired, and wherever located, and all products and proceeds (both cash and
non-cash) thereof, including without limitation all of the following (each of
the following being listed without limiting the generality of any other of the
following listed items): all of the Lessee's right, title and interest, whether
now owned or hereafter acquired or existing, in and to all books and records;
and in and to all of the following (each such term as defined in the Uniform
Commercial Code): all accounts, chattel paper, documents, instruments, general
intangibles, investment property, goods, equipment, inventory and fixtures; and
in and to all insurance premiums; and further in and to all of the Lessee's
other rights, remedies, obligations or other property of every kind and
description including without limitation all rights of Lessee to the payment of
money, causes of action or choses in action and all rights to recovery
therefrom; and in and to all consents, licenses, certificates and other
governmental approvals; and in and to all money, cash or cash equivalents and
bank accounts; and in and to all proceeds of letters of credit issued in favor
of Lessee; and including without limitation such properties and other assets
leased or otherwise subject to the Lease (including without limitation all
right, title and interest of Lessee, now owned or hereafter acquired, and
wherever located, in, to and under (a) all Properties including without
limitation all Equipment and all Fixtures, (b) all substitutions, modifications
and replacements of, and all additions, accessions and improvements to, the
Fixtures and Equipment, (c) all books and records relating to or kept in
connection with Lessee's operation of the Properties or any part thereof, (d)
all insurance premiums under insurance policies now or subsequently obtained by
Lessee including without limitation such premiums relating to the Properties or
any part thereof, (e) all awards and other compensation, including without
limitation the interest payable thereon and any right to collect and receive the
same for the taking by eminent domain, condemnation or otherwise of any and all
property including without limitation the Properties or any part thereof, (f)
all consents, licenses, certificates and other governmental approvals relating
to the construction, completion, use or operation of any and all property
including without limitation the Properties or any part thereof, (g) all Plans
and Specifications relating to any and all property including without limitation
the Properties or any part thereof, (h) all "instruments" (as defined in the
Uniform Commercial Code) relating to the Properties or any part thereof, (i) all
"documents" (as such term is defined in the Uniform Commercial Code) relating to
the Properties or any part thereof, (j) all "general intangibles" (as 

                                 Appendix A-23
<PAGE>
 
such term is defined in the Uniform Commercial Code) relating to the Properties
or any part thereof, (k) all "chattel paper" (as such term is defined in the
Uniform Commercial Code) relating to the Properties or any part thereof, (l) all
"accounts" (as such term is defined in the Uniform Commercial Code) relating to
the Properties or any part thereof, and (m) all proceeds, both cash and non-cash
of any of the foregoing).

          "Lessee Credit Agreement" shall mean that certain Third Amended and
Restated Loan Agreement dated as of December 29, 1997 among AOR, the various
lenders parties thereto from time to time and First Union National Bank, as the
agent thereunder, as such may hereafter be amended, modified, supplemented,
restated and/or refinanced or otherwise replaced from time to time.

          "Lessee Credit Agreement Event of Default" shall mean an Event of
Default as defined in Article VII of the Lessee Credit Agreement.

          "Lessor" shall mean the Owner Trustee, not in its individual capacity,
but as the Lessor under the Lease.

          "Lessor Basic Rent" shall mean the scheduled Holder Yield accrued,
outstanding and due on the Holder Advances on any Scheduled Interest Payment
Date pursuant to the Trust Agreement (but not including interest on (a) any such
scheduled Holder Yield due on the Holder Advances prior to the Rent Commencement
Date with respect to the Property to which such Holder Advances relate or (b)
overdue amounts under the Trust Agreement or otherwise).

          "Lessor Financing Statements" shall mean UCC financing statements and
fixture filings appropriately completed and executed for filing in the
applicable jurisdictions in order to protect the Lessor's interest under the
Lease to the extent the Lease is a security agreement or a mortgage.

          "Lessor Lien" shall mean any Lien, true lease or sublease or
disposition of title arising as a result of (a) any claim against the Lessor or
the Trust Company, in its individual capacity, not resulting from the
transactions contemplated by the Operative Agreements, (b) any act or omission
of the Lessor or the Trust Company, in its individual capacity, which is not
required by the Operative Agreements or is in violation of any of the terms of
the Operative Agreements, (c) any claim against the Lessor or the Trust Company,
in its individual capacity, with respect to Taxes or Transaction Expenses
against which the Lessee is not required to indemnify the Lessor or the Trust
Company, in its individual capacity, pursuant to Section 11 of the Participation
Agreement or (d) any claim against the Lessor arising out of any transfer by the
Lessor of all or any portion of the interest of the Lessor in the Properties,
the Trust Estate or the Operative Agreements other than the transfer of title to
or possession of any Properties by the Lessor pursuant to and in accordance with
the Lease, the Credit Agreement, the Security Agreement or the Participation
Agreement or pursuant to the exercise of the remedies set forth in Article XVII
of the Lease.

                                 Appendix A-24
<PAGE>
 
          "Lien" shall mean any mortgage, pledge, security interest,
encumbrance, lien, option or charge of any kind.

          "Limited Recourse Amount" shall mean with respect to all the
Properties on an aggregate basis, an amount equal to the sum of the Termination
Values with respect to all the Properties on an aggregate basis on each Payment
Date, less the Maximum Residual Guarantee Amount as of such date with respect to
all the Properties on an aggregate basis.

          "Loan Basic Rent" shall mean the scheduled interest accrued,
outstanding and due on the Loans on any Scheduled Interest Payment Date pursuant
to the Credit Agreement (but not including interest on (a) any such Loan due
prior to the Rent Commencement Date with respect to the Property to which such
Loan relates or (b) any overdue amounts under Section 2.8(c) of the Credit
Agreement or otherwise).

          "Loan Property Cost" shall mean, with respect to each Property at any
date of determination, an amount equal to (a) the aggregate principal amount of
all Loans (including without limitation all Acquisition Loans and Construction
Loans) made on or prior to such date with respect to such Property minus (b) the
aggregate amount of prepayments or repayments as the case may be of the Loans
allocated to reduce the Loan Property Cost of such Property pursuant to Section
2.6(c) of the Credit Agreement.

          "Loans" shall mean the loans extended pursuant to the Credit Agreement
and shall include both the Tranche A Loans and the Tranche B Loans.

          "Majority Holders" shall mean at any time, Holders whose Holder
Advances outstanding represent at least sixty-six and two thirds percent 
(66 2/3%) of the aggregate Holder Advances outstanding.

          "Majority Lenders" shall mean at any time, Lenders whose Loans
outstanding represent at least sixty-six and two thirds percent (66 2/3%) of the
aggregate Loans outstanding.

          "Majority Secured Parties" shall mean at any time, Lenders and Holders
whose Loans and Holder Advances outstanding represent at least sixty-six and two
thirds percent (66 2/3%) of the aggregate Advances outstanding.

          "Marketing Period" shall mean, if the Lessee has given a Sale Notice
in accordance with Section 20.1 of the Lease, the period commencing on the date
such Sale Notice is given and ending on the Expiration Date.

          "Material Adverse Effect" shall, mean a material adverse effect on (a)
the business, condition (financial or otherwise), assets, liabilities or
operations of the Credit Parties (on a consolidated basis), (b) the ability of
the Credit Parties (on a consolidated basis) to perform their collective
obligations under or in connection with the Operative Agreements, (c) the
validity, priority or enforceability of any Lien on any Property created by any
of the Operative Agreements (except this subsection (c) shall not limit the
rights of Lessee, or impose additional 

                                 Appendix A-25
<PAGE>
 
obligations on Lessee, relating to Permitted Liens and/or Lessor Liens), or (d)
the value, utility or useful life of any material portion of any Property or the
use, or ability of the Lessee to use, any material portion of any Property for
the purpose for which it was intended.

          "Maturity Date" shall mean the Expiration Date.

          "Maximum Residual Guarantee Amount" shall mean an amount equal to the
product of the aggregate Property Cost for all of Properties times eighty-five
percent (85%).

          "Modifications" shall have the meaning specified in Section 11.1(a) of
the Lease.

          "Mortgage Instrument" shall mean any mortgage, deed of trust or any
other instrument executed by the Owner Trustee and the Lessee (or regarding any
Property subject to a Ground Lease, the applicable Affiliate of the Lessee) in
favor of the Agent (for the benefit of the Lenders and the Holders) and
evidencing a Lien on the Property, in form and substance reasonably acceptable
to the Agent.

          "Multiemployer Plan" shall mean any plan described in Section
4001(a)(3) of ERISA to which contributions are or have been made or required by
any Credit Party or any of its Subsidiaries or ERISA Affiliates.

          "Multiple Employer Plan" shall mean a plan to which any Credit Party
or any ERISA Affiliate and at least one (1) other employer other than an ERISA
Affiliate is making or accruing an obligation to make, or has made or accrued an
obligation to make, contributions.

          "New Facility" shall have the meaning given to such term in Section
28.1 of the Lease.

          "Non-Integral Equipment" shall mean Equipment constituting solely
personal property which (a) is not and shall at no time during the Term become a
fixture or otherwise be deemed to constitute real property, (b) is not integral
to the operations of the Property and (c) is not radiation equipment, including
without limitation, linear accelerators, treatment simulators and other related
equipment used in the planning and delivery of external beam radiation therapy
or cancer cases that benefit from precision delivery of ionizing radiation.

          "Notes" shall mean those notes issued to the Lenders pursuant to the
Credit Agreement and shall include both the Tranche A Notes and the Tranche B
Notes.

          "Obligations" shall have the meaning given to such term in Section 1
of the Security Agreement.

          "OECD" shall mean the Organization for Economic Cooperation and
Development and any successor thereto.

          "Officer's Certificate" with respect to any Person shall mean a
certificate executed on behalf of such Person by a Responsible Officer who has
made or caused to be made such 

                                 Appendix A-26
<PAGE>
 
examination or investigation as is necessary to enable such Responsible Officer
to express an informed opinion on behalf of such Person with respect to the
subject matter of such Officer's Certificate.

          "Operative Agreements" shall mean the following: the Participation
Agreement, the Agency Agreement, the Trust Agreement, the Certificates, the
Credit Agreement, the Notes, the Lease, the Lease Supplements (and memoranda of
the Lease and each Lease Supplement in a form reasonably acceptable to the
Agent), the Accession Agreements, the Security Agreement, the Mortgage
Instruments, the other Security Documents, the Ground Leases, the Deeds and the
Bills of Sale and any and all other agreements, documents and instruments
executed in connection with any of the foregoing.

          "Original Executed Counterpart" shall have the meaning given to such
term in Section 5 of EXHIBIT A to the Lease.

          "Overdue Interest" shall mean any interest payable pursuant to Section
2.8(c) of the Credit Agreement.

          "Overdue Rate" shall mean (a) with respect to the Loan Basic Rent, and
any other amount owed under or with respect to the Credit Agreement or the
Security Documents, the rate specified in Section 2.8(b) of the Credit
Agreement, (b) with respect to the Lessor Basic Rent, the Holder Yield and any
other amount owed under or with respect to the Trust Agreement, the Holder
Overdue Rate, and (c) with respect to any other amount, the amount referred to
in clause (y) of Section 2.8(b) of the Credit Agreement.

          "Owner Trustee," "Borrower" or "Lessor" shall mean First Security
Bank, National Association, not individually, except as expressly stated in the
various Operative Agreements, but solely as the Owner Trustee under the AOR
Trust 1997-1, and any successor or replacement Owner Trustee expressly permitted
under the Operative Agreements.

          "Participant" shall have the meaning given to such term in Section 9.7
of the Credit Agreement.

          "Participation Agreement" shall mean the Participation Agreement dated
on or about the Initial Closing Date, among the Lessee, AOR, the various
entities which are parties thereto from time to time, as the other Tranche A
Guarantors, the Owner Trustee, not in its individual capacity except as
expressly stated therein, the Holders, the Lenders and the Agent.

          "Payment Date" shall mean any Scheduled Interest Payment Date and any
date on which interest or Holder Yield in connection with a prepayment of
principal on the Loans or of the Holder Advances is due under the Credit
Agreement or the Trust Agreement.

          "PBGC" shall mean the Pension Benefit Guaranty Corporation created by
Section 4002(a) of ERISA or any successor thereto.

                                 Appendix A-27
<PAGE>
 
          "Pension Plan" shall mean a "pension plan", as such term is defined in
section 3(2) of ERISA, which is subject to title IV of ERISA (other than a
Multiemployer Plan), and to which the Lessee or any ERISA Affiliate may have any
liability, including without limitation any liability by reason of having been a
substantial employer within the meaning of section 4063 of ERISA at any time
during the preceding five (5) years, or by reason of being deemed to be a
contributing sponsor under section 4069 of ERISA.

          "Permitted Facility" shall mean a cancer treatment facility of the
type and size customarily used and operated by a medical practice group that is
managed or controlled by AOR and/or any of its Wholly-Owned Entities in the
ordinary course of its business as of the Initial Closing Date.  For the purpose
of this definition, "control" means the possession, directly or indirectly, of
the power to direct or cause the direction of management and non-medical
policies, whether through the ownership of voting securities, by contract or
otherwise.  Notwithstanding the above, control shall not include, and shall not
be implied to include, the power to direct any physician's practice of medicine
or the power to interfere in any physician/patient relationship.

          "Permitted Liens" shall mean:

          (a) the respective rights and interests of the parties to the
     Operative Agreements as provided in the Operative Agreements;

          (b) the rights of any sublessee or assignee under a sublease or an
     assignment expressly permitted by the terms of the Lease for no longer than
     the duration of the Lease;

          (c) Liens for Taxes that either are not yet due or are being contested
     in accordance with the provisions of Section 13.1 of the Lease;

          (d) Liens arising by operation of law, materialmen's, mechanics',
     workmen's, repairmen's, employees', carriers', warehousemen's and other
     like Liens relating to the construction of the Improvements or in
     connection with any Modifications or arising in the ordinary course of
     business for amounts that either are not more than thirty (30) days past
     due or are being diligently contested in good faith by appropriate
     proceedings, so long as such proceedings satisfy the conditions for the
     continuation of proceedings to contest Taxes set forth in Section 13.1 of
     the Lease;

          (e) Liens of any of the types referred to in clause (d) above that
     have been bonded for not less than the full amount in dispute (or as to
     which other security arrangements satisfactory to the Lessor and the Agent
     have been made), which bonding (or arrangements) shall comply with
     applicable Legal Requirements, and shall have effectively stayed any
     execution or enforcement of such Liens;

          (f) Liens arising out of judgments or awards with respect to which
     appeals or other proceedings for review are being prosecuted in good faith
     and for the payment of 

                                 Appendix A-28
<PAGE>
 
     which adequate reserves have been provided as required by GAAP or other
     appropriate provisions have been made, so long as such proceedings have the
     effect of staying the execution of such judgments or awards and satisfy the
     conditions for the continuation of proceedings to contest Taxes set forth
     in Section 13.1 of the Lease;

          (g) Liens in favor of municipalities to the extent agreed to by the
     Lessor; and

          (h) Liens appearing on title insurance policies in favor of the Lessor
     and the Agent delivered pursuant to the Participation Agreement with
     respect to the various Properties, to the extent such Liens are reasonably
     acceptable to the Agent.

          "Person" shall mean any individual, corporation, partnership, joint
venture, association, joint stock company, trust, unincorporated organization,
governmental authority or any other entity.

          "Physician Transaction" shall mean any bona fide transaction or series
of related transactions, consummated after the date hereof, by which AOR or any
Subsidiary (a) acquires all or part of the assets, or a going business or
division, of any Person, whether through purchase of assets or securities,
merger or otherwise, (b) directly or indirectly acquires control of any Person
or (c) acquires the right to manage the non-medical aspects of the business of
any Person.  For the purpose of this definition, "control" means the possession,
directly or indirectly, of the power to direct or cause the direction of
management and non-medical policies, whether through the ownership of voting
securities, by contract or otherwise.  Notwithstanding the above, control shall
not include, and shall not be implied to include, the power to direct any
physician's practice of medicine or the power to interfere in any
physician/patient relationship.


          "Plans and Specifications" shall mean, with respect to Improvements,
the plans and specifications for such Improvements to be constructed or already
existing, as such Plans and Specifications may be amended, modified or
supplemented from time to time in accordance with the terms of the Operative
Agreements.

          "Prime Lending Rate" shall have the meaning given to such term in the
definition of ABR.

          "Property" shall mean, with respect to each Permitted Facility that is
(or is to be) acquired, constructed and/or renovated pursuant to the terms of
the Operative Agreements, the Land and each item of Equipment and the various
Improvements, in each case located on such Land, including without limitation
each Construction Period Property, each Property subject to a Ground Lease and
each Property for which the Term has commenced.

          "Property Acquisition Cost" shall mean the cost to the Lessor to
purchase a Property on a Property Closing Date.

                                 Appendix A-29
<PAGE>
 
          "Property Closing Date" shall mean the date on which the Lessor
purchases a Property or, with respect to the first Advance, the date on which
the Lessor seeks reimbursement for Property previously purchased by the Lessor.

          "Property Cost" shall mean with respect to a Property the aggregate
amount (and/or the various items and occurrences giving rise to such amounts) of
the Loan Property Cost plus the Holder Property Cost for such Property (as such
amounts shall be increased equally among all Properties respecting the Holder
Advances and the Loans extended from time to time to pay for the Transaction
Expenses, fees, expenses and other disbursements referenced in Sections 7.1(a)
and 7.1(b) of the Participation Agreement).

          "Purchase Option" shall have the meaning given to such term in Section
20.1 of the Lease.

          "Purchasing Lender" shall have the meaning given to such term in
Section 9.8(a) of the Credit Agreement.

          "Register" shall have the meaning given to such term in Section 9.9(a)
of the Credit Agreement.

          "Regulation D" shall mean Regulation D of the Board of Governors of
the Federal Reserve System (or any successor), as the same may be modified and
supplemented and in effect from time to time.

          "Release" shall mean any release, pumping, pouring, emptying,
injecting, escaping, leaching, dumping, seepage, spill, leak, flow, discharge,
disposal or emission of a Hazardous Substance.

          "Rent" shall mean, collectively, the Basic Rent and the Supplemental
Rent, in each case payable under the Lease.

          "Rent Commencement Date" shall mean, regarding each Property, the
earlier to occur of the Construction Period Termination Date and the Completion
Date.

          "Reportable Event" shall have the meaning specified in ERISA.

          "Requested Funds" shall mean any funds requested by the Lessee or the
Construction Agent, as applicable, in accordance with Section 5 of the
Participation Agreement.

          "Requisition" shall have the meaning specified in Section 4.2 of the
Participation Agreement.

          "Responsible Officer" shall mean the Chairman or Vice Chairman of the
Board of Directors, the Chairman or Vice Chairman of the Executive Committee of
the Board of Directors, the President, any Senior Vice President or Executive
Vice President, any Vice 

                                 Appendix A-30
<PAGE>
 
President, the Secretary, any Assistant Secretary, the Treasurer, or any
Assistant Treasurer, except that when used with respect to the Trust Company or
the Owner Trustee, "Responsible Officer" shall also include the Cashier, any
Assistant Cashier, any Trust Officer or Assistant Trust Officer, the Controller
and any Assistant Controller or any other officer of the Trust Company or the
Owner Trustee customarily performing functions similar to those performed by any
of the above designated officers and also means, with respect to a particular
corporate trust matter, any other officer to whom such matter is referred
because of his knowledge of and familiarity with the particular subject.

          "Sale Date" shall have the meaning given to such term in Section
20.3(a) of the Lease.

          "Sale Notice" shall mean a notice given to the Lessor in connection
with the election by the Lessee of its Sale Option.

          "Sale Option" shall have the meaning given to such term in Section
20.1 of the Lease.

          "Sale Proceeds Shortfall" shall mean the amount by which the proceeds
of a sale described in Section 22.1 of the Lease are less than the Limited
Recourse Amount with respect to the Properties if it has been determined that
the Fair Market Sales Value of the Properties at the expiration of the term of
the Lease has been impaired by greater than expected wear and tear during the
Term of the Lease.

          "Scheduled Interest Payment Date" shall mean (a) as to any Eurodollar
Loan or Eurodollar Holder Advance, the last day of the Interest Period
applicable to such Eurodollar Loan or Eurodollar Holder Advance (provided with
respect to any Eurodollar Loan or Eurodollar Holder Advance having an Interest
Period of six (6) months, the day which is three (3) months after the first day
of such Interest Period), (b) as to any ABR Loan or any ABR Holder Advance, the
fifteenth day of each month and (c) as to all Loans and Holder Advances, the
date of any voluntary or involuntary payment, prepayment, return or redemption,
and the Maturity Date or the Expiration Date, as the case may be.

          "Secured Parties" shall have the meaning given to such term in the
Security Agreement.

          "Securities Act" shall mean the Securities Act of 1933, as amended,
together with the rules and regulations promulgated thereunder.

          "Security Agreement" shall mean the Security Agreement dated on or
about the Initial Closing Date between the Lessor and the Agent, for the benefit
of the Secured Parties and accepted and agreed to by Lessee.

          "Security Documents" shall mean the collective reference to the
Security Agreement, the Mortgage Instruments, (to the extent the Lease is
construed as a security instrument) the Lease and all other security documents
hereafter delivered to the Agent granting a lien on any asset or assets
of any Person to secure the obligations and liabilities of the Lessor under the
Credit 

                                 Appendix A-31
<PAGE>
 
Agreement and/or under any of the other Credit Documents or to secure any
guarantee of any such obligations and liabilities.

          "Soft Costs" shall mean all costs which are ordinarily and reasonably
incurred in relation to the acquisition, development, installation,
construction, improvement and testing of the Properties other than Hard Costs,
including without limitation structuring fees, administrative fees, legal fees,
upfront fees, fees and expenses related to appraisals, title examinations, title
insurance, document recordation, surveys, environmental site assessments,
geotechnical soil investigations and similar costs and professional fees
customarily associated with a real estate closing, the Lender Facility Fee, the
Holder Facility Fee, fees and expenses of the Owner Trustee payable or
reimbursable under the Operative Agreements and costs and expenses incurred
pursuant to Sections 7.3(a) and 7.3(b) of the Participation Agreement.

          "Subsidiary" shall mean, as to any Person, any corporation of which at
least a majority of the outstanding stock having by the terms thereof ordinary
voting power to elect a majority of the board of directors of such corporation
(irrespective of whether or not at the time stock of any other class or classes
of such corporation shall have or might have voting power by reason of the
happening of any contingency) is at the time owned by such Person, or by one (1)
or more Subsidiaries, or by such Person and one (1) or more Subsidiaries.

          "Supplemental Amounts" shall have the meaning given to such term in
Section 9.18 of the Credit Agreement.

          "Supplemental Rent" shall mean all amounts, liabilities and
obligations (other than Basic Rent) which the Lessee assumes or agrees to pay to
the Lessor, the Trust Company, the Holders, the Agent, the Lenders or any other
Person under the Lease or under any of the other Operative Agreements including
without limitation payments of the Termination Value, the Maximum Residual
Guarantee Amount, Facility Fees, Owner Trustee fees, break-funding amounts and
all indemnification amounts, liabilities and obligations.

          "Taxes" shall have the meaning specified in the definition of
"Impositions".

          "Term" shall have the meaning specified in Section 2.2 of the Lease.

          "Termination Date" shall have the meaning specified in Section 16.2(a)
of the Lease.

          "Termination Event" shall mean (a) with respect to any Pension Plan,
the occurrence of a Reportable Event or an event described in Section 4062(e) of
ERISA, (b) the withdrawal of the Lessee or any ERISA Affiliate from a Multiple
Employer Plan during a plan year in which it was a substantial employer (as such
term is defined in Section 4001(a)(2) of ERISA), or the termination of a
Multiple Employer Plan, (c) the distribution of a notice of intent to terminate
a Plan or Multiemployer Plan pursuant to Section 4041(a)(2) or 4041A of ERISA,
(d) the institution of proceedings to terminate a Plan or Multiemployer Plan by
the PBGC under Section 4042 of ERISA, (e) any other event or condition which
might constitute grounds under Section 4042 of ERISA for
the termination of, or the appointment of a trustee to administer, any Plan or

                                 Appendix A-32
<PAGE>
 
Multiemployer Plan, or (f) the complete or partial withdrawal of any Credit
Party or any ERISA Affiliate from a Multiemployer Plan.

          "Termination Notice" shall have the meaning specified in Section 16.1
of the Lease.

          "Termination Value" shall mean at any date the sum of (a) either (i)
with respect to all Properties, an amount equal to the aggregate outstanding
Property Cost for all the Properties, in each case as of the last occurring
Payment Date, or (ii) with respect to a particular Property, an amount equal to
the product of the Termination Value of all the Properties times a fraction, the
numerator of which is the Property Cost allocable to the particular Property in
question and the denominator of which is the aggregate Property Cost for all the
Properties, in each case as of the last occurring Payment Date, plus (b)
respecting the amounts described in each of the foregoing subclause (i) or (ii),
as applicable, any and all accrued but unpaid interest to such date on the Loans
and any and all Holder Yield on the Holder Advances related to the applicable
Property Cost, plus (c) to the extent the same is not duplicative of the amounts
payable under clause (b) above, all other Rent and other amounts then due and
payable or accrued to such date under the Agency Agreement, Lease and/or under
any other Operative Agreement (including without limitation amounts under
Sections 11.1 and 11.2 of the Participation Agreement and all costs and expenses
referred to in clause FIRST of Section 22.2 of the Lease).

          "Tranche A Commitments" shall mean the obligation of the Tranche A
Lenders to make the Tranche A Loans to the Lessor in an aggregate principal
amount at any one (1) time outstanding not to exceed the aggregate of the
amounts set forth opposite each Tranche A Lender's name on Schedule 1.1 to the
Credit Agreement, as such amount may be reduced from time to time in accordance
with the provisions of the Operative Agreements; provided, no Tranche A Lender
shall be obligated to make Tranche A Loans in excess of such Tranche A Lender's
share of the Tranche A Commitments as set forth adjacent to such Tranche A
Lender's name on Schedule 1.1 to Credit Agreement.

          "Tranche A Guarantors" shall mean those parties to the Credit
Agreement from time to time as guarantors of the Tranche A Obligations,
including without limitation the Lessee and such other parties executing
Accession Agreements from time to time.

          "Tranche A Lenders" shall mean First Union National Bank and shall
include the several banks and other financial institutions from time to time
party to the Credit Agreement that commit to make the Tranche A Loans.

          "Tranche A Loans" shall mean the Loans made pursuant to the Tranche A
Commitment.

          "Tranche A Note" shall have the meaning given to it in Section 2.2 of
the Credit Agreement.

          "Tranche A Obligations" shall mean any and all obligations of the
Owner Trustee to pay any and all amounts and perform any and all obligations
regarding the Tranche A Notes, 

                                 Appendix A-33
<PAGE>
 
including without limitation to pay the principal amount, all amounts of
interest and all other amounts owing with respect thereto on the Maturity Date
or upon any earlier due date therefor.

          "Tranche B Commitments" shall mean the obligation of the Tranche B
Lenders to make the Tranche B Loans to the Lessor in an aggregate principal
amount at any one (1) time outstanding not to exceed the aggregate of the
amounts set forth opposite each Tranche B Lender's name on Schedule 1.1 to the
Credit Agreement, as such amount may be reduced from time to time in accordance
with the provisions of the Operative Agreements; provided, no Tranche B Lender
shall be obligated to make Tranche B Loans in excess of such Tranche B Lender's
share of the Tranche B Commitments as set forth adjacent to such Tranche B
Lender's name on Schedule 1.1 to Credit Agreement.

          "Tranche B Lenders" shall mean First Union National Bank and shall
include the several banks and other financial institutions from time to time
party to the Credit Agreement that commit to make the Tranche B Loans.

          "Tranche B Loan" shall mean the Loans made pursuant to the Tranche B
Commitment.

          "Tranche B Note" shall have the meaning given to it in Section 2.2 of
the Credit Agreement.

          "Transaction Expenses" shall mean all Soft Costs and all other costs
and expenses incurred in connection with the preparation, execution and delivery
of the Operative Agreements and the transactions contemplated by the Operative
Agreements including without limitation all costs and expenses described in
Sections 7.1 and 7.3 of the Participation Agreement and the following:

          (a) the reasonable fees, out-of-pocket expenses and disbursements of
     counsel in negotiating the terms of the Operative Agreements and the other
     transaction documents, preparing for the closings under, and rendering
     opinions in connection with, such transactions and in rendering other
     services customary for counsel representing parties to transactions of the
     types involved in the transactions contemplated by the Operative
     Agreements;

          (b) the reasonable fees, out-of-pocket expenses and disbursements of
     accountants for any Credit Party in connection with the transaction
     contemplated by the Operative Agreements;

          (c) any and all other reasonable fees, charges or other amounts
     payable to the Lenders, the Agent, the Holders, the Owner Trustee or any
     broker which arises under any of the Operative Agreements;

          (d) any other reasonable fee, out-of-pocket expenses, disbursement or
     cost of any party to the Operative Agreements or any of the other
     transaction documents; and

                                 Appendix A-34
<PAGE>
 
          (e) any and all Taxes and fees incurred in recording or filing any
     Operative Agreement or any other transaction document, any deed,
     declaration, mortgage, security agreement, notice or financing statement
     with any public office, registry or governmental agency in connection with
     the transactions contemplated by the Operative Agreement;

provided, however, the foregoing shall not provide for the payment of fees and
expenses of counsel to any of the Holders or the Lenders (excepting the Agent)
other than (i) after the occurrence and during the continuance of any Event of
Default and (ii) as provided for in the indemnification provisions of the
Operative Agreements (including without limitation Sections 11.1 through 11.4 of
the Participation Agreement).

          "Tribunal" shall mean any state, commonwealth, federal, foreign,
territorial, or other court or government body, subdivision agency, department,
commission, board, bureau or instrumentality of a governmental body.

          "Trust" shall mean the AOR Trust 1997-1.

          "Trust Agreement" shall mean the Trust Agreement dated on or about the
Initial Closing Date between the Holders and the Owner Trustee.

          "Trust Company" shall mean First Security Bank, National Association,
in its individual capacity, and any successor owner trustee under the Trust
Agreement in its individual capacity.

          "Trust Estate" shall have the meaning specified in Section 2.2 of the
Trust Agreement.

          "Type" shall mean, as to any Loan, whether it is an ABR Loan or a
Eurodollar Loan.

          "UCC Financing Statements" shall mean collectively the Lender
Financing Statements and the Lessor Financing Statements.

          "Unanimous Vote Matters" shall have the meaning given it in Section
12.4 of the Participation Agreement.

          "Unfunded Amount" shall have the meaning specified in Section 3.2 of
the Agency Agreement.

          "Unfunded Liability" shall mean, with respect to any Plan, at any
time, the amount (if any) by which (a) the present value of all benefits under
such Plan exceeds (b) the fair market value of all Plan assets allocable to such
benefits, all determined as of the then most recent valuation date for such
Plan, but only to the extent that such excess represents a potential liability
of the Company or any member of the Controlled Group to the PBGC or such Plan
under Title IV of ERISA.

          "Uniform Commercial Code" and "UCC" shall mean the Uniform Commercial
Code as in effect in any applicable jurisdiction.

                                 Appendix A-35
<PAGE>
 
          "United States Bankruptcy Code" shall mean Title 11 of the United
States Code.

          "U.S. Person" shall have the meaning specified in Section 11.2(e) of
the Participation Agreement.

          "U.S. Taxes" shall have the meaning specified in Section 11.2(e) of
the Participation Agreement.

          "Wholly-Owned Entity" shall mean a Person all of the shares of capital
stock or other ownership interest of which are owned by AOR and/or one of its
wholly-owned Subsidiaries or other wholly-owned entities.

          "Withholdings" shall have the meaning specified in Section 11.2(e) of
the Participation Agreement.

          "Work" shall mean the furnishing of labor, materials, components,
furniture, furnishings, fixtures, appliances, machinery, equipment, tools,
power, water, fuel, lubricants, supplies, goods and/or services with respect to
any Property.

                                 Appendix A-36