<PAGE>   1


                                                                   EXHIBIT 10.1



THIS CONTRACT CONTAINS INDEMNIFICATION PROVISIONS.  READ IT CAREFULLY.

                        OFFICE BUILDING LEASE AGREEMENT
                            BASIC LEASE INFORMATION


LEASE DATE:                OCTOBER 16 , 1996

TENANT:                    ILEX ONCOLOGY, INC., A DELAWARE CORPORATION

TENANT ADDRESS:            11550 IH 10 WEST, SUITE 300
                           SAN ANTONIO, TEXAS  78230

CONTACT:                   JAMES KOCH            TELEPHONE: (210) 677-6080

LANDLORD:                  N.W.A.  LIMITED PARTNERSHIP

LANDLORD'S ADDRESS:        11550 IH 10 WEST , SUITE 185
                           SAN ANTONIO, TEXAS  78230

CONTACT:                   BUILDING MANAGER           TELEPHONE: (210) 694-4024

PREMISES:                  Suite No. 300 deemed to contain 21,036 square feet
                           of Rentable Area (as hereinafter defined), the same
                           being of 18,291 square feet of Usable Area (as
                           hereinafter defined); and

                           Effective July 1, 1997, Suite 170 deemed to contain
                           2,962 square feet of Rentable Area (as hereinafter
                           defined), the same being of 2,576 square feet of
                           Usable Area (as hereinafter defined).

                           Suites 300 and 170 are outlined on the plan attached
                           to the Lease as Exhibit A, and are located in the
                           office building (the "Building") located on the land
                           described as, NCB 17442, BLK 1, LOT 1, NW OFFICE
                           PARK UT-1, BEXAR COUNTY, TEXAS and known as
                           NORTHWEST ATRIUM OFFICE BUILDING, 11550 IH- 10 WEST
                           street (the "Land").

TERM:                      The period of sixty (60) months commencing JANUARY
                           1, 1997 (the "Commencement Date") and ending at 5:00
                           p.m. DECEMBER 31, 2001 subject to adjustment or
                           earlier termination as provided in the Lease.











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BASIC RENTAL:              Basic Rental shall be payable in monthly
                           installments, and subject to escalation's (if any),
                           as follows:

<TABLE>
<CAPTION>
                           MONTHLY                  MONTHLY              MONTHLY
                           PERIOD                  BASE RENTAL          RATE/RSF
                           -----------------------------------------------------
<S>                        <C>                      <C>                  <C>  
                           1-12
                           THRU 6/30/97             $21,456.72           $1.02
                           7/1/97 & THEREAFTER      $24,477.96           $1.02
                           13-24                    $25,677.86           $1.07
                           25-36                    $26,877.76           $1.12
                           37-48                    $28.077.66           $1.17
                           49-60                    $29,277.56           $1.22
</TABLE>

EXPENSE STOP:              $5.89 per RSF (which is applicable to the
                           calculation of Excess Oprating Expense [hereinafter
                           defined] payable by Tenant)

SECURITY DEPOSIT:          $27,275.54

RENT:                      Basic Rental and all other sums that Tenant may owe
                           to Landlord under the Lease.

PERMITTED USE:             GENERAL BUSINESS OFFICES

TENANTS                    FROM THE COMMENCEMENT DATE THROUGH JUNE 30, 1997:
PROPORTIONATE
SHARE                      22.76% which is the percentage obtained by dividing
                           (i) 21,036 the square feet of Rentable Area in the
                           Premises by (ii) the total 92,410 square feet of
                           Rentable Area in the Building.

                           BEGINNING JULY 1, 1997:

                           25.97 % which is the percentage obtained by dividing
                           (i) 23,998 square feet of Rentable Area in the
                           Premises by (ii) the total 92,410 square feet of
                           Rentable Area in the Building.

APPURTENANT
FACILITIES:                The parking areas, driveways, landscaping,
                           sidewalks, and other facilities now or hereafter
                           located on the Land (other that the Building) which
                           are used in connection with the operation of the
                           Building.










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BROKER:                    RFM Commercial, Inc. and Mission City Properties,
                           Inc.

SPECIAL PROVISIONS:        The Parties hereto understand and agree that the
                           formula specified in other provisions of this lease
                           would yield a Rentable Area of more than
                           23,998square feet due to the number of square feet
                           occupied by the atrium in the Building. Nonetheless,
                           the parties have agreed that, notwithstanding any
                           other provisions in this lease to the contrary, the
                           Rentable Area shall for all purposes, be deemed to
                           be 21,036 square feet for Suite 300 and 2,962 square
                           feet for Suite 170 for a total of 23,998 square
                           feet.

                           Tenant shall have 30 days from the date of the
                           execution of the Lease to measure the Usable Area
                           and the Rentable Area and to check the Tenant's
                           Proportionate Share. If Tenant does not protest in
                           writing within 30 days of the date of this Lease the
                           Usable Area, Rentable Area and/or the Tenant's
                           Proportionate share, specified in this Lease, then
                           Tenant has agreed to the same and may not thereafter
                           raise any issue regarding the correctness of the
                           same.

                           Subject to Landlord's approval, Tenant may select
                           the local exchange supplier to supply its
                           telecommunication needs. Tenant shall have the right
                           to install a satellite dish on the existing poles on
                           the roof of the Building and to employ the
                           mechanical chases of the Building to the Premises
                           provided that: (i) the dish shall not exceed
                           thirty-six inches in diameter; and (ii) the dish
                           shall be located and screened so as not to be
                           visible from adjoining properties.

                           Prior to the Commencement Date, Landlord agrees to
                           repair and repaint the water- stained area below the
                           top of the atrium of the Building.

                           Landlord represents that to the best of its actual
                           knowledge, the Building is structurally sound.











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THE FOREGOING BASIC LEASE INFORMATION IS INCORPORATED INTO AND MADE A PART OF
THE LEASE, BUT DOES NOT CONSTITUTE THE ENTIRE LEASE. TENANT ACKNOWLEDGES THAT
IT HAS READ ALL OF THE PROVISIONS CONTAINED IN THE ENTIRE LEASE AND ALL
EXHIBITS WHICH ARE A PART THEREOF AND AGREES THAT THIS LEASE , INCLUDING THE
BASIC LEASE INFORMATION AND ALL EXHIBITS, REFLECT THE ENTIRE UNDERSTANDING AND
REASONABLE EXPECTATIONS OF LANDLORD AND TENANT REGARDING THE PREMISES. IN THE
EVENT ANY CONFLICT EXISTS BETWEEN ANY BASIC LEASE INFORMATION AND THE LEASE,
THEN THE LEASE SHALL CONTROl.

N.W.A. LIMITED PARTNERSHIP                 ILEX ONCOLOGY, INC., a Delaware Corp.
(Landlord)                                 (Tenant)


By:                                        By:
    ----------------------------------        ---------------------------------
IRIS S. STEWART
VICE PRESIDENT OF ITS                         ---------------------------------
GENERAL PARTNER                                    Printed Name
GEORGE INVESTMENT GROUP, INC.
                                              ---------------------------------
                                                     Title

EXHIBITS:
Exhibit "A"                Outline of Premises
Exhibit "B"                Building Rules and Regulations
Exhibit "C"                Workletter for Suite 300
Exhibit "D"                Parking Agreement
Exhibit "E"                Workletter for Suite 170










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<PAGE>   5



                                    OFFICE BUILDING LEASE AGREEMENT


                  THIS OFFICE BUILDING LEASE AGREEMENT (the "Lease") is entered
                  into as of October 16, 1996, between NWA Limited Partnership
                  ("Landlord"), and ILEX Oncology, Inc., a Delaware Corporation
                  , ("Tenant").

DEFINITIONS
AND BASIC

PROVISIONS        1.       a. BASIC LEASE INFORMATION. The definitions and basic
                  provisions set forth in the Basic Lease Information ( "Basic
                  Lease Information") executed by Landlord and Tenant
                  contemporaneously herewith are incorporated herein by
                  reference for all purposes.

                           b. RENTABLE AREa.   "Rentable Area" refers to the
                  square footage or areas within the Building determined by
                  adding the following: (i) the Usable Area (as defined below)
                  of the area being measured, (ii) the portion of the
                  Building-Shared Areas (as defined below) allocable to the
                  area being measured, and (iii) the portion of the
                  Floor-Shared Areas (as defined below) allocable to the area
                  being measured.

                           c. USABLE AREa. "Usable Area" means the square
                  footage of the areas in the Premises (including areas for the
                  specific use of "Tenant" and installed at the request of
                  "Tenant" such as special stairs or elevators) or other areas
                  held for lease measured from the inside surface of the outer
                  glass, finished column or exterior wall of the Building
                  enclosing the Premises (a) to the inside surface of the
                  opposite outer glass, finished column or exterior wall, or
                  (b) to the mid-point of the demising walls separating the
                  Premises from: (i) areas leased to or held for lease to other
                  tenants, (ii) Building-Shared Areas, (iii) Floor-Shared
                  Areas, and (iv) Service Areas (as defined below), as the case
                  may be. No deductions from Usable Area shall be made for
                  columns or projections necessary to the Building.

                           d. SERVICE AREAS. "Service Areas" means the square
                  footage of the areas within (and measured from the mid-point
                  of the walls enclosing) the Building stairs, fire towers,
                  elevator shafts, flues, vents, stacks, pipe shafts, vertical
                  ducts and other vertical penetrations. Areas for the specific
                  use of a tenant and installed at the request of a tenant such
                  as special stairs or elevators are not included within the
                  definition of Service Areas, and such areas will be included
                  in the Usable Area of the space being measured.

                           e. BUILDING-SHARED AREAS. "Building-Shared Areas"
                  means the square footage of the areas within (and measured
                  from the mid-point of the walls enclosing) the Building
                  elevator, machine rooms, main mechanical and electrical
                  rooms, public lobbies, and other areas not leased or held for
                  lease within the Building and not included in Service Areas
                  or Floor-Shared Areas, but which are necessary or desirable
                  for the proper utilization of the Building or to provide
                  customary services to the Building. The allocation to the
                  Premises of the Building-Shared Areas shall be equal to the
                  total Building-Shared Areas within the Building multiplied by
                  a fraction, the numerator of which is the Usable Area of the
                  Premises and the denominator of which is the total Usable
                  Area of the Building.





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                           f. FLOOR-SHARED AREAS. "Floor-Shared Areas" means
                  the square footage of the areas within (and measured from the
                  mid-point of the walls enclosing) public corridors, elevator
                  foyers, rest rooms, mechanical rooms, janitor closets,
                  telephone and equipment rooms, and other similar facilities
                  for the use of all tenants on the floor on which the Premises
                  are located and which are not included in Service Areas or
                  Usable Area of a particular tenant. In the case of a floor
                  leased to more than one tenant, the allocation to the
                  Premises of the Floor-Shared Areas on said floor shall be
                  equal to the total Floor-Shared Areas on said floor
                  multiplied by a fraction, the numerator of which is the
                  Usable Area of the Premises located on said floor and the
                  denominator of which is the total Usable Area of said floor.

                           g. STIPULATIONS AS TO AREa. Landlord and Tenant
                  hereby agree that the Rentable Area of the Premises has been
                  calculated on the basis of the foregoing definitions to be
                  the number of square feet of Rentable Area for the Premises
                  set forth in the Basic Lease information.

LEASE

GRANT             2. Subject to the terms of this Lease, Landlord leases to 
                  Tenant, and Tenant leases from Landlord, the Premises for the
                  Term (as same may be renewed as set forth herein). In
                  addition, Tenant shall have the non-exclusive right, along
                  with Landlord and all other tenants in the Building and their
                  invitees, to use areas designated by Landlord to be the
                  common areas in the Building and the Appurtenant Facilities,
                  except any portions thereof designated for the use of
                  specific tenants, such as the portion of the corridor on the
                  northern one-half of the third (3rd) floor that is set aside
                  for Tenant, as set out in the Plans. Tenant and Landlord
                  agree that Tenant may establish a card access system to the
                  corridor on the North Side of the Third Floor and exclude
                  other tenants and invitees of the Building from such space
                  without same being deemed a part of the Premises for the
                  purposes of calculations of rent or of Tenant's Proportionate
                  Share.

COMMENCEMENT
DATE              3.       If the Commencement Date is not the first day of a 
                  calendar month, then the Term shall be extended by the time
                  between the Commencement Date and the first day of the next
                  month. In the event Tenant occupies the Premises prior to the
                  scheduled Commencement Date, the Commencement Date shall be
                  defined as the date such occupancy commences. If this Lease
                  is executed before the Premises become vacant or otherwise
                  available and ready for occupancy by Tenant, or if any
                  present occupant of the Premises holds over and Landlord
                  cannot acquire possession of the Premises before the
                  Commencement Date, then (a) Tenant's obligation to pay Rent
                  hereunder shall be waived until Landlord tenders possession
                  of the Premises to Tenant, (b) the Term shall be extended by
                  the time between the scheduled Commencement Date and the date
                  on which Landlord tenders possession of the Premises to
                  Tenant (which date will then be defined as the Commencement
                  Date), (c) Landlord shall not be in default hereunder or be
                  liable for damages therefor, and (d) Tenant shall accept
                  possession of the Premises when Landlord tenders possession
                  thereof to the Tenant. With the exception of the Temporary
                  Space, by occupying the Premises, Tenant shall be deemed to
                  have accepted the Premises in their condition as of the date
                  of such occupancy, subject to the performance of punch-list
                  items that remain to be performed by Landlord, if any,
                  Landlord shall have the right, but not the









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                  obligation, to deliver to Tenant a letter (the "Confirmation
                  Letter" ) confirming (i) the Commencement Date, (ii) that
                  Tenant has accepted the Premises, and (iii) that Landlord has
                  performed all of its obligations, if any, with respect to the
                  condition of the Premises (except for punch-list items
                  specified in such Confirmation Letter). All information set
                  forth in the Confirmation Letter shall be deemed correct and
                  binding on both Landlord and Tenant, unless Tenant objects to
                  any such information in writing to Landlord within ten (10)
                  days of Tenant's receipt of the Confirmation Letter. If
                  requested by Landlord, Tenant shall execute and deliver to
                  Landlord, within ten (10) days after Landlord has requested
                  same, a copy of the Confirmation Letter, although Tenant's
                  failure to execute or deliver the same shall not limit the
                  binding nature thereof if Tenant fails to object in writing
                  to any information set forth therein within the time period
                  provided in this Section 3.

RENT              4.       a. PAYMENT. Tenant shall timely pay to Landlord the 
                  Basic Rental and all additional sums to be paid by Tenant to
                  Landlord under this Lease, including the amounts set forth in
                  Section 4b., without notice, demand, counterclaim, set-off or
                  abatement, at Landlord's Address (or such other address as
                  Landlord may from time to time designate in writing to
                  Tenant). Basic Rental, adjusted as herein provided, shall be
                  payable monthly in advance. The first monthly installment of
                  Basic Rental shall be payable contemporaneously with the
                  execution of this Lease, and a like monthly installment of
                  Basic Rental shall be due on the first day of the second full
                  calendar month of the Term and continuing thereafter on the
                  first day of each succeeding calendar month during the Term.
                  Basic Rental for any fractional month at the beginning of the
                  Term shall be prorated and shall be due on the Commencement
                  Date. In the event the Commencement Date is not the first day
                  of a calendar month, Tenant shall pay as Basic Rental for any
                  such partial month a prorated rental in an amount equal to
                  $715.22 for each day remaining in said month. Tenant's
                  obligation to pay Rent hereunder is an independent covenant.

                           b. OPERATING EXPENSE ESCALATOR. Tenant shall pay an
                  amount equal to the excess ("Excess Operating Expense") of
                  Tenant's Proportionate Share of the actual Operating Expenses
                  for each calendar year or part thereof during the Term, over
                  the Expense Stop. Landlord may collect such amount in a lump
                  sum, to be due within thirty (30) days after Landlord
                  furnishes to Tenant the annual statement of actual Operating
                  Expenses. Alternatively, Landlord may make a good faith
                  estimate of the Excess Operating Expenses to be due by Tenant
                  for any calendar year or part thereof during the Term, and,
                  unless Landlord delivers to Tenant a revision of the
                  estimated Excess Operating Expense, Tenant shall pay to
                  landlord, on the Commencement Date and on the first day of
                  calendar month thereafter, an amount equal to the estimated
                  Excess Operating Expense for such calendar year or part
                  thereof divided by the number of months in such calendar year
                  during the Term. From time to time during any calendar year,
                  Landlord may estimate and re-estimate the Excess Operating
                  Expense to be due by Tenant for the calendar year and deliver
                  a copy of the estimate or re-estimate to Tenant. Thereafter,
                  the monthly installments of Excess Operating Expense payable
                  by Tenant shall be appropriately adjusted in accordance









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                  with the estimations so that, by the end of the calendar year
                  in question, Tenant shall have paid all of the Excess
                  Operating Expense as estimated by Landlord. Any amounts paid
                  based on such an estimate shall be subject to adjustment
                  pursuant to Section 4d. when actual Operating Expenses are
                  available of each calendar year.

                           c. OPERATING EXPENSES. For the purposes of this
                  Section 4, the term "Operating Expenses" shall mean all
                  expenses and disbursements of every kind (subject to the
                  limitations set forth below) which Landlord incurs, pays or
                  becomes obligated to pay in connection with the ownership,
                  operation, and maintenance of the Building and Appurtenant
                  Facilities, determined in accordance with generally accepted
                  accounting principles consistently applied, including but not
                  limited to the following:

                           (i) The costs (including wages and salaries and the
                           taxes, insurance and benefits relating thereto) of
                           those employees of the Building or Landlord who are
                           engaged in the operation, repair, replacement,
                           maintenance, and security of the Building and
                           Appurtenant Facilities, including management fees;

                           (ii) All tools, equipment, supplies and materials
                           used in the operation, maintenance, repair,
                           replacement, and security of the Building and
                           Appurtenant Facilities;

                           (iii) Actual cost of all capital improvements made
                           to the Building and Appurtenant Facilities which
                           although capital in nature can reasonably be
                           expected to reduce the normal operating costs of the
                           Building and Appurtenant Facilities, as well as all
                           capital improvements made in order to comply with
                           any law hereafter promulgated by any governmental
                           authority relating to energy, conservation, public
                           safety or security. Provided, however, the amount of
                           such costs that may be included as operating costs
                           in any one year is limited to the ratio of one
                           divided by the useful economic life of such
                           improvements as determined by Landlord in its
                           reasonable discretion (without regard to the period
                           over which such improvements may be depreciated or
                           amortized for federal income tax purposes) times the
                           cost of the item;

                           (iv) Cost of all utilities for the Building and
                           Appurtenant Facilities, including the cost of water,
                           sewer and power for heating, lighting, air
                           conditioning and ventilating (excluding those costs
                           billed to specific tenants);

                           (v) Cost of any Insurance or Insurance related
                           expense applicable to the Building and Appurtenant
                           Facilities and Landlord's personal property used in
                           connection therewith;

                           (vi) All taxes and assessments and governmental
                           charges whether federal, state, county or municipal,
                           and whether they be by taxing authorities presently
                           taxing or by others subsequently created or
                           otherwise, and any other taxes and assessments









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                           directly attributable to the Land, Building,
                           Appurtenant Facilities or rents from the operation
                           and leasing thereof, exclusive of Direct Taxes
                           (defined in 4e, below) federal or state income
                           taxes, or taxes that are imposed on Landlord by
                           reason of its form of organization (collectively,
                           "Taxes"). If the present method of taxation changes
                           such that in lieu of the whole or any part of ad
                           valorem taxes, there is imposed on owners of real
                           property a tax or taxes assessed and levied that
                           such tax is directly attributable to the Land, the
                           Building, the Appurtenant Facilities or the rental
                           from the operation or leasing thereof, the amount of
                           such tax so attributable shall be included as part
                           of the Taxes to be included as Operating Expenses to
                           be reimbursed by the Tenants of the Building.

                           (vii) Cost of repairs, replacements, and general
                           maintenance of the Building and Appurtenant
                           Facilities; and

                           (viii) Cost of service or maintenance contracts with
                           independent contractors for the operation,
                           maintenance, repair, replacement, or security of the
                           Building and Appurtenant Facilities (including,
                           without limitation, alarm service, window cleaning,
                           and elevator maintenance).

                  There are specifically excluded from the definition of the
                  term "Operating Expenses" costs (1) for capital improvements
                  made to the Building, other than capital improvements
                  described in subparagraph (iii) above and except for items
                  which, though capital for accounting purposes, are properly
                  considered maintenance and repair items, such as painting of
                  common areas, replacement of carpet in elevator lobbies,
                  corridors and the like; (2) for repair, replacements and
                  general maintenance paid by proceeds of insurance or by
                  Tenant or other third parties, and alterations attributable
                  solely to tenants of the Building other than Tenant; (3) for
                  interest, amortization or other payments on loans to
                  Landlord; (4) for depreciation of the Building; (5) for
                  leasing commissions; (6) for legal fees other than those
                  incurred for the purpose of reducing Operating Expenses
                  (e.g., legal fees incurred in contesting the assessment of
                  Taxes); (7) for renovating or otherwise improving space for
                  occupants of the Building or vacant space in the Building;
                  (8) for correcting defects in the construction of the
                  Building, such as any repairs or modifications arising out of
                  foundation problems; and (9) for federal income taxes imposed
                  on or measured by the income of landlord from the operation
                  of the Building. Tenant, at Tenant's sole cost and expense,
                  shall have the right to audit Landlord's books and records
                  relating to Operating Expenses and Landlord agrees to make
                  available to Tenant, upon at least ten (10) days proper
                  written notice from Tenant to Landlord, its books and records
                  relevant to such an audit.

                           d.  ADJUSTMENT.  The annual cost statement shall 
                  include a statement of Landlord's actual Operating Expenses
                  for the previous year. If the annual cost statement reveals
                  that Tenant paid more for Operating Expenses than the actual
                  Excess Operating Expense in the year for which such statement
                  was prepared, then Landlord, shall credit









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                  against future Excess Operating Expenses or, upon notice from
                  Tenant, Landlord shall reimburse Tenant for such excess;
                  likewise, if Tenant paid less than the actual Excess
                  Operating Expense, then Tenant shall pay Landlord such
                  deficiency either of such payments to be made within thirty
                  (30) days after delivery of such annual cost statement.

                           e. DIRECT TAXES. At the same time and in the same
                  manner as the payment of Basic Rental hereunder, Tenant shall
                  pay any gross revenue tax, sales tax, excise tax, value-added
                  tax, privilege tax, or similar tax imposed by any government
                  or governmental agency upon Tenant on account of the Lease or
                  the payment of Rent hereunder ("Direct Taxes").

                           f. SURVIVABILITY OF OBLIGATIONS.  All obligations of
                  Tenant to pay Rent accrued prior to termination of this Lease
                  shall survive such termination.

DELINQUENT
PAYMENT,
LATE
CHARGES           5.       a.  All Rent to be paid by Tenant to Landlord shall
                  be in lawful money of the United States of America and shall
                  be paid without deduction or offset, prior notice or demand,
                  at the address set forth in the Basic Lease Information, or
                  at such other places as may be designated from time to time
                  by Landlord. In the event a check is submitted by Tenant for
                  payment, and is returned for insufficient funds, a $25.00
                  handling fee will be assessed by Landlord. If thereafter a
                  second check is returned for insufficient funds, another
                  handling fee in the amount of $25.00 will be assessed, and
                  all future payments thereafter must be made in cash or by
                  cashier's or certified check. In the event any Rent is not
                  received within ten (10) days after its due date for any
                  reason whatsoever, then in addition to the past due amount
                  Tenant shall pay to Landlord interest on the Rent then past
                  due at a rate equal to the lesser of (i) 18% per annum, or
                  (ii) the maximum contractual rate which could legally be
                  charged in the event of a loan of such Rent to Tenant, such
                  interest to accrue continuously on any unpaid balance due to
                  Landlord by Tenant during the period commencing with the Rent
                  due date and terminating with the date on which Tenant makes
                  full payment of all amounts owing to Landlord at the time of
                  said payment. Any such late charge or interest payment shall
                  be payable as additional Rent under this Lease and shall be
                  payable immediately on demand. In no event, however, shall
                  the charges permitted under this Section 5 or elsewhere in
                  this Lease, to the extent the same are considered to be
                  interest under applicable law, exceed the maximum lawful
                  contract rate of interest.

SECURITY
DEPOSIT           6.       Contemporaneously with the execution of this Lease,
                  Tenant shall pay to Landlord, in immediately available funds,
                  the Security Deposit, which shall be held by Landlord without
                  liability for interest and as security for the performance by
                  Tenant of its obligations under this Lease. The Security
                  Deposit is not an advance payment of Rent or a measure or
                  limit of Landlord's damages upon an Event of Default (defined
                  below). Landlord shall not be obligated to hold the Security
                  Deposit as a separate fund, but may commingle it with other
                  funds. Landlord may, from time to time and without prejudice
                  to any other remedy, use all or a part of the Security
                  Deposit to perform any obligation which Tenant was obligated,
                  but failed, to perform hereunder.




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                  Following any such application of the Security Deposit,
                  Tenant shall pay to Landlord on demand the amount so applied
                  in order to restore the Security Deposit to its original
                  amount. Within a reasonable time after the Term ends,
                  provided Tenant has performed all of its obligations
                  hereunder, Landlord shall return to Tenant the balance of the
                  Security Deposit not applied to satisfy Tenant's obligations.
                  If Landlord transfers its interest in the Premises, then
                  Landlord may assign the Security Deposit to the transferee
                  and Landlord thereafter shall have no further liability for
                  the return of the Security Deposit.

LANDLORD'S        7.       a. SERVICES.  Provided no Event of Default exists,
                  Landlord shall use reasonable efforts OBLIGATIONS to furnish
                  to Tenant (i) water (hot and cold) at those points of supply
                  provided for general use of tenants of the Building, as
                  modified by the work to be performed in accordance with
                  Tenant's Final Plans; (ii) heated and refrigerated air
                  conditioning as appropriate, at such times as Landlord
                  normally furnishes these services to all tenants of the
                  Building, and at such temperatures and in such amounts as are
                  reasonably considered by Landlord to be standard; (iii)
                  janitorial service to the Premises five nights a week except
                  on Holidays (Landlord reserves the right to bill Tenant
                  separately for extra janitorial service required for
                  non-standard installations) and such window washing as may
                  from time to time in Landlord's judgment be reasonably
                  required; (iv) elevators for ingress and egress to the floor
                  on which the Premises are located, in common with other
                  tenants, provided that Landlord may reasonably limit the
                  number of elevators to be in operation at times other than
                  during normal business hours and on holidays; (v) replacement
                  of Building-standard light bulbs and fluorescent tubes; and
                  (vi) electrical current during normal business hours other
                  than for equipment whose electrical energy consumption
                  exceeds normal office usage, Landlord agrees that the
                  electrical energy consumption needs depicted on Tenant's
                  Final Plans does not exceed normal office usage. Landlord
                  shall maintain the common areas of the Building first quality
                  condition (Tenant agrees that the Building is in first
                  quality condition as of the Commencement Date), except for
                  damage occasioned by Tenant, or its employees, agents or
                  invitees. Landlord and Tenant disclaim all implied warranties
                  that the premises are suitable for Tenant's intended
                  commercial use. If Tenant desires any of the services
                  specified in this Section 7a. at any time other than times
                  herein designated (or as specified as normal business hours
                  in rules and regulations attached hereto), Landlord shall use
                  reasonable efforts to supply such services to Tenant upon the
                  written request of Tenant delivered to Landlord before 3:00
                  p.m. on the business day for which such extra usage is
                  requested, or before 3:00 p.m. on Fridays for weekend use and
                  3:00 p.m. on the last business day before Holiday use. Within
                  ten (10) days after Landlord has delivered an invoice
                  therefor, Tenant shall pay to Landlord the actual cost
                  incurred by Landlord for such services.

                           b. EXCESS UTILITY USE. If Tenant's requirements for 
                  or consumption of electricity exceed the electricity to be
                  provided by Landlord as described in Section 7a.,




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                  Landlord shall, at Tenant's expense, make reasonable efforts
                  to supply such service through the then-existing feeders and
                  risers serving the Building and the Premises, and Tenant
                  shall pay to Landlord the cost of such service within ten
                  (10) days after Landlord has delivered to Tenant an invoice
                  therefor. Tenant shall not install any electrical equipment
                  requiring special wiring or requiring voltage in excess of
                  110 volts or otherwise exceeding Building capacity unless
                  approved in advance by Landlord. The use of electricity in
                  the Premises shall not exceed the capacity of existing
                  feeders and risers to or wiring in the Premises. Any riders
                  or wiring required to meet Tenant's excess electrical
                  requirements shall, upon Tenant's written request, be
                  installed by landlord, at Tenant's cost, if, in Landlord's
                  sole and absolute judgment, the same are necessary and shall
                  not cause permanent damage or injury to the Building or the
                  Premises, cause or create a dangerous or hazardous condition,
                  entail excessive or unreasonable alterations, repairs, or
                  expenses, or interfere with or disturb other tenants of the
                  Building. If Tenant uses machines or equipment in the
                  Premises which require additional air conditioning capacity
                  above that provided by the Building standard system, Tenant
                  shall pay the costs of additional air conditioning
                  installation and operating costs.

                          c.  DISCONTINUANCE.  Landlord's obligation to 
                  furnish utility services under Section 7a. shall be subject
                  to the rules and regulations of the supplier of such services
                  and governmental rules and regulations.

                          d. RESTORATION OF SERVICES; ABATEMENT. Landlord shall 
                  use reasonable efforts to restore any service that becomes
                  unavailable; however, such unavailability shall not render
                  Landlord liable for any damages caused thereby, be a
                  constructive eviction of Tenant, constitute a breach of any
                  implied warranty, or entitle Tenant to any abatement of
                  Tenant's obligations hereunder, including but not limited to
                  Tenant's obligation to pay Rent.

                          e. Since Suite 170 may experience differential 
                  shifting, Landlord agrees that any cosmetic repairs required
                  due to shifting will be made by Landlord throughout the Term
                  of the Lease.

IMPROVEMENTS;
ALTERATIONS;
 REPAIRS;         8.       a. IMPROVEMENTS; ALTERATIONS.  Except as otherwise 
                  specified in this Lease or in any Exhibit hereto,
                  improvements to the Premises shall be installed at the
                  expense of Tenant only in accordance with plans and
                  specifications which have been previously submitted to and
                  MAINTENANCE approved in writing by Landlord. After the
                  initial Tenant improvements are made (if any), no alterations
                  or physical additions in or to the Premises may be made
                  without Landlord's prior written consent. Tenant shall not
                  paint or install lighting or decorations, signs, window or
                  door lettering, or advertising media of any type on or about
                  the Premises that is visible to the





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                  common areas of the Building without the prior written
                  consent of Landlord. All alterations, additions, or
                  improvements, (whether temporary or permanent in character,
                  and including without limitation all air-conditioning
                  equipment and all other equipment that is in any ;manner
                  connected to the Building's plumbing system) made in or upon
                  the Premises either by Landlord or Tenant, shall be
                  Landlord's property at the end of the Term and shall remain
                  on the Premises without compensation to Tenant; provided,
                  however, that if Tenant is not then in default hereunder and
                  Tenant repairs any damage caused by such removal, Tenant may
                  remove its trade fixtures at the end of the Term. Approval by
                  Landlord of any of Tenant's drawing and plans and
                  specifications prepared in connection with any improvements
                  in the Premises shall not constitute a representation or
                  warranty of Landlord as to the adequacy or sufficiency of
                  such drawings, plans and specifications, or the improvements
                  to which they relate, for any use, purpose, or condition, but
                  such approval shall merely be the consent of Landlord as
                  required hereunder. To the best of Landlord's actual
                  knowledge, the Building is substantially in compliance with
                  applicable local, state and federal laws, rules, regulations
                  and decrees.


                        b. REPAIRS; MAINTENANCE. Tenant shall maintain the 
                  Premises in a clean, safe, operable, attractive condition,
                  and shall not permit or allow to remain any waste or damage
                  to any portion of the Premises. Landlord shall, at its own
                  expense (but subject to Landlord's right to reimbursement for
                  maintenance expenses constituting Operating Expenses),
                  maintain the exterior walls and the structure, electrical,
                  plumbing and mechanical systems of the Building provided that
                  Tenant shall repair or replace, subject to Landlord's
                  direction and supervision, any damage to the Building or any
                  of its systems caused by Tenant or Tenant's agents,
                  contractors, or invitees. If Tenant fails to make such
                  repairs or replacements within thirty (30) days after the
                  occurrence of such damage or if such damage cannot be
                  repaired within such thirty (30) day period for non-monetary
                  reasons only, if Tenant does not commence to make such
                  repairs and thereafter diligently prosecute such repairs
                  within such thirty (30) day period, then Landlord may make
                  the same at Tenant's cost. Such cost shall be limited to only
                  reasonable cost, but which may include an additional fee
                  equal to 15% of the cost for Landlord's overhead expense if
                  Landlord serves as the general contractor on such repair, and
                  shall be payable to Landlord within ten (10) days after
                  Landlord has delivered to Tenant an invoice therefor.

                        c. PERFORMANCE OF WORK. All work described in this 
                  Section 8 shall be performed only by Landlord or by
                  contractors and subcontractors approved in writing by
                  Landlord. Tenant shall cause all contractors and
                  subcontractors to procure and maintain insurance coverage
                  against such risks, in such amounts, and with such companies
                  as Landlord may reasonably require. In addition, for
                  contracts for work with a cost of more than $20,000.00, at
                  Landlord's request,



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                  Tenant shall cause all contractors and subcontractors to
                  procure payment and performance bonds reasonably satisfactory
                  to Landlord covering the cost of the work. All such work
                  shall be performed in accordance with all legal requirements
                  and in a good and workmanlike manner so as not to damage the
                  Premises, the primary structure or structural qualities of
                  the Building, or plumbing, electrical lines, or other utility
                  transmission facility.

                           d. MECHANIC'S LIENS. Tenant shall not permit any 

                  mechanic's liens to be filed against the Premises or the
                  Building for any work performed, materials furnished, or
                  obligation incurred by or at the request of Tenant. If such a
                  lien is filed, then Tenant shall, within ten (10) days after
                  Landlord has delivered notice of the filing to Tenant, either
                  pay the amount of the lien or diligently contest such lien
                  and deliver to Landlord a bond or other security reasonably
                  satisfactory to Landlord. If Tenant elects to contest such
                  lien and if a statutory proceeding exists for the release of
                  the lien by the posting of a bond, Tenant shall immediately
                  proceed to obtain a release of said lien in accordance with
                  such statute. If Tenant fails either to timely pay the lien
                  amount or diligently contest such lien and deliver the
                  required bond or security, then Landlord may pay the lien
                  claim without inquiry as to the validity thereof, and any
                  amounts so paid, including expenses and interest, shall be
                  paid by Tenant to Landlord within ten (10) days after
                  Landlord has delivered to Tenant an invoice therefor. Nothing
                  contained in this Lease will be deemed the consent or
                  agreement of Landlord, nor shall Tenant be deemed to have any
                  authority, to subject Landlord's interest in the Premises or
                  the Building to the imposition of any lien, or otherwise to
                  liability, under any mechanics' or other lien law.

USE               9.       a. PERMITTED USE / COMPLIANCE WITH LAWS.   Tenant 
                  shall continuously occupy and use the Premises only for the
                  Permitted Use and shall comply with all laws, orders, rules,
                  and regulations relating to the use, condition, and occupancy
                  of the Premises. Landlord covenants that it will comply with
                  all laws, rules, regulations, ordinances and decrees of
                  local, state or federal authorities applicable to the
                  Building as a whole. Tenant shall comply with any direction
                  of any governmental authority having jurisdiction over the
                  Premises, which shall by reason of the nature of Tenant's use
                  or occupancy of the Premises, impose any duty upon Tenant or
                  Landlord with respect to the Premises or the occupancy
                  thereof. Tenant shall not do or permit anything to be done
                  which would invalidate or increase the cost of any fire,
                  extended coverage, or any other insurance policy covering the
                  Building. Notwithstanding the foregoing and without limiting
                  the remedies of Landlord for a violation of the provisions of
                  this Section 9a., Tenant shall promptly, upon demand
                  reimburse Landlord for the full amount of any additional
                  premium charged for such policy by reason of Tenant's failure
                  to comply with the provisions of this Section 9a. Tenant
                  shall not in any way obstruct or interfere with the rights or
                  other



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                  tenants or occupants of the Building, or use or allow the
                  Premises to be used for any improper, immoral or
                  objectionable purpose nor shall Tenant cause, maintain or
                  permit any nuisance in, on or about the Premises.

                           b. HAZARDOUS MATERIALS. The Premises shall not be 
                  used for any use which is disreputable or creates
                  extraordinary fire hazards or results in an increased rate of
                  insurance on the Building or its contents or the storage of
                  any Hazardous Materials (as defined below). Without limiting
                  the foregoing, Tenant shall not cause or permit any Hazardous
                  Material to be brought upon, kept or used in or about the
                  Premises or Building or Appurtenant Facilities or the Land by
                  Tenant, its employees, agents, contractors or invitees. As
                  used herein, the term "Hazardous Materials" shall mean any
                  hazardous or toxic substance, material or waste, including
                  but not limited to, those substances, materials and wastes
                  now or hereafter listed in the United States Department of
                  Transportation Hazardous Materials Table or by the
                  Environmental Protection Agency as hazardous substances, or
                  such substances, materials and wastes that are or become
                  regulated under any applicable federal, state or local law,
                  exclusive of solvents and chemicals customarily used and
                  consumed in an office building. Tenant expressly covenants
                  that Tenant will advise Landlord immediately upon learning
                  that any Hazardous Material has been brought upon the
                  Premises or Building or Appurtenant Facilities or the Land,
                  whether or not caused or permitted by Tenant and regardless
                  of who shall have brought such Hazardous Materials thereon.
                  If Tenant permits any Hazardous Material to be brought upon,
                  kept or used in or about the Premises or Building or
                  Appurtenant Facilities or the Land, then Tenant shall take
                  all steps reasonably necessary to safeguard against their
                  discharge and Tenant shall indemnify, defend and hold
                  Landlord harmless from any and all claims, judgments,
                  damages, penalties, fines, costs, liabilities or losses,
                  including but not limited to, diminution in value of the
                  Premises or Building or Appurtenant Facilities or the Land,
                  damages for loss or restriction on use of rentable or usable
                  space or of any amenity in the Premises or Building or
                  Appurtenant Facilities or the Land, damages arising from any
                  adverse impact on marketing of the Premises or Building or
                  Appurtenant Facilities or the land, and sums paid in
                  settlement of claims, attorneys' fees, consulting fees and
                  expert fees, which arise during or after the Term as a result
                  of such contamination. This indemnification of Landlord by
                  Tenant includes but is not limited to costs incurred in
                  connection with any investigation of sight conditions or
                  clean-up, remedial removal or restoration work required by
                  any federal, state or local government agency or political
                  subdivision because of Hazardous Material present in the
                  Premises or Building or Appurtenant Facilities or the Land,
                  or the soil or ground water on which the Building is located.
                  Without limiting the foregoing, if the presence of any
                  Hazardous Material on the Premises or Building or Appurtenant
                  Facilities or the Land caused or permitted by Tenant results
                  in any contamination of the Premises or Building or
                  Appurtenant Facilities or the Land, Tenant shall, upon
                  request by Landlord, promptly take all









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                  actions at its sole expense that are necessary to return the
                  Premises or Building or Appurtenant Facilities or the Land to
                  the condition existing prior to the introduction or exposure
                  of any Hazardous Material in the Premises or Building or
                  Appurtenant Facilities or the Land. The indemnity provision
                  set forth in this Section 9b. shall survive termination or
                  expiration of this Lease.

ASSIGNMENT
AND
SUBLETTING        10.   a. ASSIGNMENT OR SUBLEASE. Except as provided in
                  paragraph (e) below, without the prior written consent of
                  Landlord, which will not be unreasonable withheld or delayed,
                  Tenant shall not assign this Lease or sublet the Premises or
                  any part thereof. Any attempted assignment or sublease by
                  Tenant in violation of the terms and conditions of this
                  paragraph shall be void and of no effect. If Tenant desires
                  to assign this Lease or sublet the Premises or any part
                  thereof, Tenant shall deliver to Landlord written notice
                  thereof (together with all of the terms of the proposed
                  assignment or sublease, the identify of the proposed
                  transferee and sufficient financial information regarding the
                  proposed transferee to permit Landlord to evaluate the
                  creditworthiness thereof) at lease sixty (60) days in advance
                  of the date on which Tenant desires to make such assignment
                  or sublease. Landlord shall have thirty (30) days following
                  receipt of such notice and information within which to notify
                  Tenant in writing that Landlord elects either to (i) permit
                  Tenant to assign this Lease or sublet such space; or (ii)
                  refuse to consent to such assignment or sublease and to
                  continue this Lease in full force and effect as to the entire
                  Premises. If Landlord fails to notify Tenant of its election
                  within such thirty (30) day period, Landlord shall be deemed
                  to have elected option (ii) above. Anything to the contrary
                  notwithstanding, Tenant shall have the right to assign or
                  sublease the Premises to any legal entity which is a wholly
                  owned subsidiary, or an affiliate, a successor corporation or
                  legal entity or which is the surviving entity following a
                  merger, consolidation or reorganization of its form of
                  organization (a "Permitted Assignee") without prior consent
                  of the Landlord, but with thirty (30) days prior written
                  notice to Landlord so long as such Permitted Assignee assumes
                  the obligations of Tenant hereunder and Tenant either agrees
                  to remain liable hereunder or, if Tenant seeks to be released
                  of its obligations hereunder, provides evidence at the time
                  it notifies Landlord of its intent to assign or sublet the
                  Premises that the Permitted Assignee is of equal or greater
                  creditworthiness.

                           b. CONSENT. The consent by Landlord to a particular
                  assignment or sublease shall not be deemed consent to any
                  other assignment or sublease. If Landlord consents to a
                  proposed assignment or sublease, then the proposed transferee
                  shall deliver to Landlord a written agreement whereby it
                  expressly assumes the Tenant's obligations hereunder;
                  however, any transferee of less than all of the space in the
                  Premises shall be liable only for obligations under this
                  Lease that are properly allocable to the space subject to the
                  assignment of sublease, and only to the extent of the rent it
                  has agreed to pay Tenant therefor.

                           c. ADDITIONAL COMPENSATION.  Tenant shall pay 
                  Landlord, immediately upon









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                  receipt thereof, all compensation received by Tenant for an
                  assignment or sublease that exceeds the Rent allocable to the
                  portion of the Premises covered thereby.

                           d. CONTINUED LIABILITY. Tenant shall, despite any
                  permitted assignment or sublease, remain directly and
                  primarily liable for the performance of all of the covenants,
                  duties, and obligations of Tenant hereunder, and Landlord
                  shall be permitted to enforce the provisions of this Lease
                  against Tenant or any assignee or sublessee without demand
                  upon or proceeding in any way against any other person.

                           e. TRANSFER OF CONTROLLING INTEREST. So long as
                  Tenant is a privately held corporation (and except with
                  respect to: (i) a sublease or assignment to a Permitted
                  Assignee; or (ii) in connection with (a) an offering of
                  securities made pursuant to exemption from registration under
                  federal or state securities laws and rules; (b) an offering
                  of securities registered in compliance with federal or state
                  securities law; (c) entry into voting trust or similar
                  covenants or agreements executed in connection with loan or
                  other venture capital arrangements or as a result of the
                  exercise of rights or remedies of the holders or
                  beneficiaries of such securities, covenants or agreements).,
                  any change in a majority of the voting rights or other
                  controlling rights or interests of Tenant shall be deemed an
                  assignment for the purposes hereof. If Tenant should become a
                  public company, the shares of which are traded on a
                  recognized stock exchange in the United States or automated
                  quotation dealer system or that is required to register its
                  stock with the United States Securities and Exchange
                  Commission under Section 12(g) of the Securities and Exchange
                  Act of 1934, this provision 10e shall no longer be effective.

INSURANCE;
 WAIVERS; 
SUBROGATION 
INDEMNITY.        11.      a. INSURANCE.  Tenant shall at its expense procure 
                  and maintain throughout the Term the following insurance
                  policies; (i) comprehensive general liability insurance in
                  amounts of not less than a combined single limit of
                  $1,000,000.00 or such other amounts as Landlord may from time
                  to time (but not more frequently then once per calendar year
                  and by notice given at least ninety (90) days prior to an
                  anniversary of the Commencement Date) reasonably require,
                  insuring Tenant, Landlord, and Landlord's agents against all
                  liability for injury to or death of a person or persons or
                  damage to property arising from the use and occupancy of the
                  Premises, Building, Appurtenant Facilities or Land, and which
                  shall name Landlord as an additional insured, (ii)
                  contractual liability insurance coverage in amounts of not
                  less than a combined single limit of $1,000,000.00 or such
                  other amounts as Landlord may from time to time reasonably
                  require to cover Tenant's indemnity obligations hereunder,
                  (iii) if Tenant operates owned, leased, hired or non-owned
                  vehicles on the Premises, comprehensive automobile liability
                  insurance at a limit of liability not less than $1,000,000.00
                  combined bodily injury and property damages, (iv) insurance
                  covering the full value of Tenant's property and
                  improvements, and other property (including property


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                  of others), in the Premises, and (v) workers compensation
                  insurance with an endorsement to waive subrogation in favor
                  of Landlord. Tenant's insurance shall provide primary
                  coverage to landlord when any policy issued to Landlord
                  provides duplicate or similar coverage, and in such
                  circumstance Landlord's policy will be excess over Tenant's
                  policy. Tenant shall furnish certificates of such insurance
                  (including all endorsements) and such other evidence
                  satisfactory to Landlord of the maintenance of all insurance
                  coverage required hereunder, and Tenant shall obtain a
                  written obligation on the part of each insurance company to
                  notify Landlord at least 30 days before cancellation or a
                  material change of any such insurance. All such insurance
                  policies shall be in form, and issued by companies licensed
                  in the State of Texas and rated not lower than A-, Class X,
                  by Best's rating service. Tenant may carry such insurance
                  under a blanket policy, provided such insurance has a
                  landlord's protective liability endorsement attached thereto.
                  If Tenant fails to procure and maintain said insurance,
                  Landlord may, but shall not be required to, procure and
                  maintain same, but at the expense of Tenant. No policy shall
                  be cancelable or subject to reduction of coverage except
                  after thirty (30) days prior written notice to Landlord.

                           b. WAIVER; NO SUBROGATION. LANDLORD SHALL NOT BE
                  LIABLE TO TENANT OR THOSE CLAIMING BY, THROUGH, OR UNDER
                  TENANT FOR ANY INJURY TO OR DEATH OF ANY PERSON OR PERSONS OR
                  THE DAMAGE TO OR THEFT, DESTRUCTION, LOSS, OR LOSS OF USE OF
                  ANY PROPERTY (A "LOSS") CAUSED BY CASUALTY, THEFT, FIRE, OR
                  THIRD PARTIES, OR BY ANY OTHER MATTER BEYOND THE REASONABLE
                  CONTROL OF LANDLORD, OR FOR ANY INJURY OR DAMAGE OR
                  INCONVENIENCE WHICH MAY ARISE THROUGH REPAIR OR ALTERATION OF
                  ANY PART OF THE BUILDING, OR FAILURE TO MAKE REPAIRS, OR FROM
                  ANY OTHER CAUSE, EXCEPT IF SUCH LOSS IS CAUSED BY LANDLORD'S
                  GROSS NEGLIGENCE OR WILLFUL MISCONDUCT. TENANT WAIVES ANY
                  CLAIM IT MIGHT HAVE AGAINST LANDLORD FOR ANY DAMAGE TO OR
                  THEFT, DESTRUCTION, LOSS, OR LOSS OF USE OF ANY PROPERTY, TO
                  THE EXTENT THE SAME IS INSURED AGAINST UNDER ANY INSURANCE
                  POLICY THAT COVERS THE BUILDING, THE PREMISES, LANDLORD'S OR
                  TENANT FIXTURES, PERSONAL PROPERTY, LEASEHOLD IMPROVEMENTS,
                  OR BUSINESS, OR IS REQUIRED TO BE INSURED AGAINST UNDER THE
                  TERMS HEREOF, REGARDLESS OF WHETHER THE NEGLIGENCE OR FAULT
                  OF THE OTHER PARTY CAUSED SUCH LOSS. Landlord and Tenant
                  shall cause their property and casualty insurance carrier to
                  endorse all applicable policies waiving the carrier's rights
                  of recovery under subrogation or otherwise against the other.

                           c. INDEMNITY. Subject to Section 11b., Tenant shall
                  defend, indemnify, and hold harmless Landlord and its agents
                  from and against all claims, demands, liabilities, causes of
                  action, suits, judgments, and expenses (including attorney's
                  fees) for any Loss arising from any occurrence on the
                  Premises, Building, Appurtenant Facilities or Land, or from
                  Tenant's failure to perform its obligations under this Lease
                  (other than a Loss arising from the sole or gross negligence
                  of Landlord or its agents), even though caused or alleged to
                  be









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                  caused by the joint, comparative, or concurrent negligence or
                  fault of Landlord or its agents, and even though any such
                  claim, cause of action, or suit is based upon or alleged to
                  be based upon the strict liability of Landlord or its agents.
                  This indemnity provision is intended to indemnify Landlord
                  and its agents against the consequences of their own
                  negligence or fault as provided above when Landlord or its
                  agents are jointly, comparatively, or concurrently negligent
                  with Tenant. This indemnity provision shall survive
                  termination or expiration of this Lease. The indemnity
                  obligations in this paragraph 11(c) are limited to the extent
                  of the greater of (i) the coverage and dollar limits of
                  insurance which Tenant has obtained or (ii) the coverage and
                  dollar limits of insurance which Tenant is obligated to
                  obtain pursuant to the provisions of this Lease.

SUBORDINATION
ATTORNMENT; 
NOTICE TO         12.      a. SUBORDINATION. This Lease shall be and is hereby 
                  made subordinate to any deed of trust, mortgage, or other
                  security instrument (a "Mortgage"), or any ground lease,
                  master lease, LANDLORD'S or primary lease (a "Primary
                  Lease"), that now or hereafter covers all or any part of the
                  MORTGAGEE Premises (the mortgagee under any Mortgage or the
                  lessor under any Primary Lease is referred to herein as
                  "Landlord's Mortgagee").

                           b. ATTORNMENT. Tenant shall attorn to any party
                  succeeding to Landlord's interest in the Premises, whether by
                  purchase, foreclosure, deed in lieu of foreclosure, power of
                  sale, termination of lease, or otherwise, upon such party's
                  request, and shall execute such agreements confirming such
                  Attornment as such party may reasonably request provided that
                  in such agreement the succeeding party agrees not to disturb
                  Tenant's right to possession of the Premises so long as
                  Tenant is not in default hereunder. In the event of such
                  request upon Tenant's Attornment as aforesaid, Tenant will
                  automatically become the tenant of the successor to
                  Landlord's interest without change in the terms or provisions
                  of this Lease; provided, however, that such successor to
                  Landlord's interest shall not be bound by (a) any payment of
                  Rent for more than one month in advance (except prepayments
                  for security deposits, if any), (b) any amendments or
                  modifications of this Lease made without the prior written
                  consent of Landlord's Mortgagee if Tenant was advised of the
                  interest of the same, or (c) any credits, offsets, defenses
                  or claims which Tenant may have against Landlord.

                           c. NOTICE TO LANDLORD'S MORTGAGEE. Tenant shall not
                  seek to enforce any remedy it may have for any default on the
                  part of the Landlord without first giving written notice by
                  certified mail, return receipt requested, specifying the
                  default in reasonable detail, to any Landlord's Mortgagee
                  whose address has been given to Tenant, and affording such
                  Landlord's Mortgagee a reasonable opportunity to perform
                  Landlord's obligations hereunder.

                           d. CERTIFICATES REQUESTED BY LANDLORD'S MORTGAGEE.
                  From time to time, Tenant shall furnish to any Landlord's
                  Mortgagee, within 10 days after a request therefor, such
                  estoppel certificates, non-disturbance and attornment
                  agreements, or other certificates as Landlord's Mortgagee may
                  reasonably request, so long as the same are accurate.

RULES AND
REGULATIONS       13.  Tenant shall comply with the rules and regulations of
                  the Building which are attached hereto as Exhibit b. Landlord
                  may, from time to time, change such rules and regulations for
                  the safety, care, or cleanliness of the Building and related
                  facilities, provided that such changes are generally
                  applicable to all tenants of the Building and will not
                  unreasonably interfere with Tenant's use of the Premises.
                  Tenant shall be responsible for the compliance with such
                  rules and regulations by its employees, agents, and invitees.
                  Landlord shall not be responsible to Tenant for the failure
                  or refusal by any tenant or other



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                  person in the Building or Appurtenant Facilities to comply
                  with the rules and regulations established by Landlord.

CONDEMNATION
                  14. If all or substantially all of the Premises and/or
                  parking area shall be taken by condemnation or conveyed in
                  lieu thereof (hereafter for the purposes of this provision, a
                  "taking"), this Lease shall terminate as of the date
                  possession is taken by the condemning authority and all rent
                  and other charges payable by Tenant shall be prorated as of
                  such date. All compensation paid for such taking (other than
                  amounts specifically paid for Tenant's leasehold
                  improvements) shall be the property of Landlord. Any amounts
                  specifically awarded for Tenant's leasehold improvements
                  shall be Tenant's property. If a portion of the Premises
                  and/or parking area is taken, but Tenant is still able,
                  reasonably, to use the remainder for the purposes for which
                  the same is leased pursuant to this Lease, then this Lease
                  shall remain in full force and effect, but rent shall be
                  equitably adjusted based upon the portion of the Premises
                  taken and the loss of utility thereof. If such a substantial
                  portion of the Premises and/or parking area is taken such
                  that Tenant may not reasonably use the Premises for the
                  purposes for which they are leased, then this Lease shall
                  terminate as provided above. For the purposes of this
                  paragraph, Landlord and Tenant agree that (i) a taking of
                  12.5% or more of the Premises or (ii) a taking which results
                  in a 12.5% or more reduction in the number of parking spaces
                  which Landlord can provide to Tenant on the Land or in close
                  proximity to the Land, will result in Tenant not being able
                  to reasonably use the Premises for the purposes for which
                  they are leased.

FIRE OR           15.      a. REPAIR ESTIMATE.  If the Premises or the Building
OTHER             are damaged by fire or other casualty (a "Casualty"), 
                  Landlord shall, within thirty (30) days after such Casualty,
                  deliver CASUALTY to Tenant a good faith estimate (the "Damage
                  Notice") of the time needed to repair the damage caused by
                  such Casualty (such estimate shall take into consideration
                  the estimated time to resolve any insurance claim and to
                  obtain the approval of Landlord's Mortgagee to the
                  application of insurance proceeds to the reconstruction of
                  the Building and Premises) and whether Landlord has
                  alternative space that might be occupied by Tenant during
                  reconstruction.

                  b. LANDLORD'S AND TENANT'S RIGHTS. If a material portion of
                  the Premises or the Building are damaged by Casualty such
                  that Tenant is prevented from conducting its business in the
                  Premises in a manner reasonably comparable to that conducted
                  immediately before such Casualty, the Damage Notice which the
                  Landlord delivers to Tenant shall include the Landlord's
                  statement that either (a) the Lease is terminated if, in
                  Landlord's judgment, any one or more of the following is
                  true: (i) the damage cannot be repaired within 180 days after
                  the date of the casualty, (ii) the expected insurance
                  settlement, together with other money the Landlord is willing
                  to commit to the rebuilding is insufficient to accomplish the
                  restoration of the building, or (iii) the Landlord's
                  mortgagee is unwilling to permit Landlord to use the
                  insurance proceeds for the restoration and the Landlord is
                  unwilling or unable to provide other funds for that purpose,
                  or (b) Landlord intends to continue the Lease if one or more
                  of the




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                  following is true: (i) Landlord has alternate space within
                  the building sufficient to provide for the Tenant's needs and
                  agrees that Tenant can occupy this space for the longer of
                  the time required for restoration or the balance of the then
                  term or renewal term of this Lease; or (ii) the repairs can
                  reasonably be expected to be accomplished within 180 days
                  after the date of the casualty based on the estimate of a
                  reputable contractor , the Landlord has received reasonable
                  assurance from its insurance carrier that the casualty claim
                  will be timely processed for payment and either Landlord's
                  mortgagee has agreed to the application of the insurance
                  proceeds to the restoration of the building or Landlord has
                  other funds available . Within fifteen days of the Damage
                  Notice Tenant may terminate the Lease only if; (i) as to a
                  Landlord notice described in b(ii) above, Tenant reasonably
                  believes the repairs cannot be completed within 180 days
                  after the date of the Casualty, or (ii) as to a Landlord
                  notice described in b(i) above, Tenant has reasonably
                  concluded that the alternate space is not reasonably
                  acceptable to Tenant. If the Lease is terminated, the rent
                  and other charges shall be abated as of the date of the
                  Casualty. If alternate space is to be provided, the rental
                  for same should be equitably adjusted and paid in lieu of
                  rent on the Premises.

                           c. REPAIR OBLIGATION. If neither party elects to
                  terminate this Lease following a Casualty, then Landlord
                  shall, within a reasonable time after such Casualty, commence
                  to repair the Building and the Premises and shall proceed
                  with reasonable diligence to restore the Building and
                  Premises to substantially the same condition as they existed
                  immediately before such Casualty; however, Landlord shall not
                  be required to repair or replace any part of the furniture,
                  equipment, fixtures, and other improvements which may have
                  been placed by, or at the request of, Tenant or other
                  occupants in the Building or the Premises, and Landlord's
                  obligation to repair or restore the Building or Premises
                  shall be limited to the extent of the insurance proceeds
                  actually received by Landlord for the Casualty in question.

TAXES             16.  Tenant shall be liable for all taxes levied and assessed
                  against personal property, furniture, or fixtures, or above
                  Building standard tenant improvements, placed by Tenant in
                  the Premises following the work to be performed pursuant to
                  Tenant's Final Plans attached, and all taxes relating to the
                  operation of Tenant's business in the Premises including,
                  without limitation, all withholding taxes and sales and use
                  taxes. If any taxes for which Tenant is liable are levied or
                  assessed against Landlord or Landlord's property and Landlord
                  elects to pay the same, or if the assessed value of
                  Landlord's property is increased by inclusion of such
                  personal property, furniture or fixtures, or above Building
                  standard tenant improvements, and Landlord elects to pay the
                  taxes based on such increase, then Tenant shall pay to
                  Landlord, upon demand, that part of such taxes for which
                  Tenant is primarily liable hereunder.










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EVENTS OF 
DEFAULT           17.  Each of the following occurrences shall constitute an 
                  "Event of Default": 


                           a. Tenant's failure to pay Rent to Landlord under 
                  the Lease when due; provided that Landlord shall not exercise
                  any remedies with respect to such Event of Default unless the
                  same remains uncured for a period of five (5) days after
                  Landlord has delivered written notice thereof; provided
                  further, however, that Landlord may exercise any such
                  remedies without any obligation of Landlord to give any
                  notice if Landlord has given Tenant written notice under this
                  Section 17a. on more than two (2) occasions during the
                  12-month interval preceding such failure by Tenant;

                           b. Tenant's failure to perform, comply with, or
                  observe any other agreement or obligation of Tenant under
                  this Lease; provided that Landlord shall not exercise any
                  remedies with respect to such Event of Default unless the
                  same remains uncured for a period of twenty (20) days after
                  Landlord delivers to Tenant written notice thereof or, if
                  such non-monetary default is of a type that cannot be cured
                  within such twenty (20) day period, and Tenant fails to
                  commence to cure such default within such twenty (20) day
                  period and thereafter diligently prosecute the cure of such
                  default;

                           c. The filing of a petition by or against Tenant
                  (the term "Tenant" shall include, for the purpose of this
                  Section 17c, any guarantor of the Tenant's obligations
                  hereunder) (i) in any bankruptcy or other insolvency
                  proceeding; (ii) seeking any relief under any state or
                  federal debtor relief law; (iii) for the appointment of a
                  liquidator or receiver for all or substantially all of
                  Tenant's property or for Tenant's interest in this Lease; or
                  (iv) for the reorganization or modification of Tenant's
                  capital structure; provided, however, if such petition is
                  filed against Tenant, then such filing shall not be an Event
                  of Default unless Tenant fails to have the proceedings
                  initiated by such petition dismissed within sixty (60) days
                  after the filing thereof; and provided further, however, that
                  an event described in this Section 17c. shall not constitute
                  an Event of Default if applicable law provides that such
                  event cannot be the basis of default hereunder;

                           d. Tenant shall vacate or abandon any portion of the 
                  Premises and discontinue the payment of Basic Rental therefor;

                           e. The admission by Tenant that it cannot meet its 
                  obligations as they become due or the making by Tenant of an
                  assignment for the benefit of its creditors; or

                           f. Any representation or warranty made by Tenant, or
                  made by any guarantor of Tenant's obligations hereunder, was
                  materially false or inaccurate when made.

REMEDIES          18. Upon any Event of Default, Landlord may, in addition to
                  all other rights and remedies afforded Landlord hereunder or
                  by law or equity, take any of the following actions:

                           a. Terminate this Lease by giving Tenant written 
                  notice thereof, in which event,



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<PAGE>   23

                  Tenant shall pay to Landlord the sum of (i) all Rent accrued
                  hereunder through the date of termination, (ii) all amounts
                  due under Section 19a., and (iii) an amount equal to (a) the
                  total Rent that Tenant would have been required to pay for
                  the remainder of the Term discounted to present value at a
                  per annum rate equal to the "Prime Rate" as published on the
                  date this Lease is terminated by The Wall Street Journal in
                  its listing of "Money Rates", minus (b) the then present fair
                  rental value of the Premises for such period, similarly
                  discounted; or

                           b. Terminate Tenant's right to possession of the
                  Premises without terminating this Lease by giving written
                  notice thereof to Tenant, in which event Tenant shall pay to
                  Landlord (i) all Rent and other amounts accrued hereunder to
                  the date of termination of possession, (ii) all amounts due
                  from time to time under Section 19a., and (iii) all Rent and
                  other sums required hereunder to be paid by Tenant during the
                  remainder of the Term, diminished by any net sums thereafter
                  received by Landlord through reletting the Premises during
                  such period. To the extent required by law, Landlord shall
                  use reasonable efforts to relet the Premises on such terms
                  and conditions as Landlord in its sole discretion may
                  determine (including a term different from the Term,
                  reasonable rental concessions, and reasonable alterations to,
                  and reasonable improvement of, the Premises); however,
                  Landlord shall not be obligated to relet or attempt to relet
                  the Premises before leasing other portions of the Building.
                  Landlord shall not be liable for, nor shall Tenant's
                  obligations hereunder be diminished because of, Landlord's
                  failure to relet the Premises or to collect rent due for such
                  reletting. Tenant shall not be entitled to the excess of any
                  consideration obtained by reletting over the Rent due
                  hereunder. Reentry by Landlord in the Premises shall not
                  affect Tenant's obligations hereunder for the unexpired Term;
                  rather, Landlord may, from time to time, bring action against
                  Tenant to collect amounts due by Tenant, without the
                  necessity of Landlord's waiting until the expiration of the
                  Term. Unless Landlord delivers written notice to Tenant
                  expressly stating that it has elected to terminate this
                  Lease, all actions taken by Landlord to exclude or dispossess
                  Tenant of the Premises shall be deemed to be taken under this
                  Section 18b. If Landlord elects to proceed under this Section
                  18b., it may at any time elect to terminate this Lease under
                  Section 18a.

                           c. Additionally, unless otherwise required by
                  applicable law, Landlord may, without notice, enter upon the
                  Premises and alter locks or other security devices at the
                  Premises to deprive Tenant, its officers, employees, agents,
                  invitees, licensees and all other occupants, of access
                  thereto. If Landlord or its agent changes the door lock of
                  Tenant following a default in the payment of rent, Landlord
                  or its agent shall place a written notice on the Tenant's
                  front door stating the name and the address or telephone
                  number of the individual or company from which the new key
                  may be obtained. The new key is required to be provided only
                  during the Tenant's regular business hours and only if Tenant
                  pays the delinquent rent plus late fees.

PAYMENT BY        
TENANT; 
NON-WAIVER        19.      a. PAYMENT BY TENANT. Upon any Event of Default, 
                  Tenant shall pay to Landlord all costs incurred Landlord
                  (including court costs at all trial and appellate levels



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                  and reasonable attorneys' fees and expenses, regardless of
                  whether suit is filed) in (i) obtaining possession of the
                  Premises, (ii) removing and storing Tenant's or any other
                  occupant's property, (iii) repairing, restoring, altering,
                  remodeling, or otherwise putting the Premises into condition
                  acceptable to a new tenant, (iv) if Tenant is dispossessed of
                  the Premises and this Lease is not terminated, reletting all
                  or any part of the Premises (including brokerage commissions,
                  cost of tenant finish work, and other costs incidental to
                  such reletting), (v) performing Tenant's obligations which
                  Tenant failed to perform, and (vi) enforcing, or obtaining
                  advice of, its rights, remedies, and recourses arising out of
                  the Event of Default.

                           b. NO WAIVER. Landlord's acceptance of Rent
                  following an Event of Default shall not waive Landlord's
                  rights regarding such Event of Default. No waiver by either
                  party of any violation or breach of any of the terms
                  contained herein shall waive either party's rights regarding
                  any future violation of such term or violation of any other
                  term.

LANDLORD'S LIEN   20.  This paragraph is intentionally left blank.

SURRENDER OF 
PREMISES          21.  No act by Landlord shall be deemed an acceptance of a
                  surrender of the Premises, and no agreement to accept a
                  surrender of the Premises shall be valid unless the same is
                  made in writing and signed by Landlord. At the
                  expiration or termination of this Lease, Tenant shall deliver
                  to Landlord the Premises with all improvements located
                  thereon in good repair and condition, reasonable wear and
                  tear (and condemnation and fire or other casualty damage not
                  caused by Tenant, as to which Sections 14 and 15 shall
                  control) excepted, and shall deliver to Landlord all keys to
                  the Premises. Provided that Tenant has performed all of its
                  obligations hereunder, Tenant may remove all trade fixtures
                  and all unattached furniture and personal property placed in
                  the Premises by Tenant (but Tenant shall not remove any such
                  item which was paid for, in whole or in part, by Landlord),
                  and shall remove such alterations, additions, improvements,
                  trade fixtures, equipment, and furniture as Landlord may
                  request. Tenant shall repair all damage caused by such
                  removal. All items not so removed shall be deemed to have
                  been abandoned by Tenant and may be appropriated, sold,
                  stored, destroyed, or otherwise disposed of by Landlord
                  without notice to Tenant and without any obligation to
                  account for such items. The provisions of this Section 21
                  shall survive the end of the Term.

HOLDING OVER      22.   If Tenant fails to vacate the Premises at the end of
                  the Term, then Tenant shall be a tenant at will and, in
                  addition to all other damages and remedies to which Landlord
                  may be entitled for such holding over, Tenant shall pay, in
                  addition to the other Rent, a daily Basic Rental equal to the
                  greater of (a) 150% of the daily Basic Rental payable during
                  the last month of the Term, OR (b) the prevailing rental rate
                  in the Building for similar space. In the event of any
                  unauthorized holding over, Tenant shall be liable to Landlord
                  for all damages which Landlord suffers as a result thereof
                  and Tenant shall indemnify Landlord against all claims made
                  by any other tenant or prospective tenant against Landlord
                  resulting from delay by Landlord in delivering possession of
                  the Premises to such other tenant or prospective tenant.

CERTAIN RIGHTS 
RESERVED BY 
LANDLORD          23.  Landlord shall have the following rights:

                           a. To decorate and to make inspections, repairs, 
                  alterations, additions, changes, or improvements, whether
                  structural or otherwise, in and about the Building, or any
                  part thereof; for such purposes, to enter upon the Premises
                  and, during the continuance of any such work, to temporarily
                  close doors, entryways, public space, and corridors in the
                  Building; to interrupt or temporarily suspend Building
                  services and facilities; and to change the arrangement and
                  location of entrances or passageways, doors, and doorways,
                  corridors, elevators, stairs, restrooms, or other public
                  parts of the Building. In its exercise of its rights,
                  Landlord





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                  agrees to use reasonable efforts under the circumstances to
                  provide advance notice of the interruption of services and to
                  attempt to minimize the disruption of the operation of the
                  tenants of the Building. In connection with changing the
                  arrangement of entranceways, passageways and other common
                  areas of the Building, Landlord agrees not to materially
                  alter the Premises or the access thereto;

                           b. To take such reasonable measures as Landlord
                  deems advisable for the security of the Building and its
                  occupants, including without limitation searching all persons
                  entering or leaving the Building; evacuating the Building for
                  cause, suspected cause, or for drill purposes; temporarily
                  denying access to the Building; and closing the Building
                  after normal business hours and on Saturdays, Sundays, and
                  holidays, subject, however, to Tenant's right to enter when
                  the Building is closed after normal business hours under such
                  reasonable regulations as Landlord may prescribe from time to
                  time which may include by way of example, but not of
                  limitation, that persons entering or leaving the Building,
                  whether or not during normal business hours, identify
                  themselves to a security officer by registration or otherwise
                  and that such persons establish their right to enter or leave
                  the Building;

                           c.  To change the name by which the Building is
                  designated; and

                           d. To enter the Premises at all reasonable hours to
                  inspect same to assure Tenant's compliance with its
                  obligations hereunder or show the Premises to prospective
                  purchasers, lenders, or tenants and to perform all services,
                  maintenance and repairs required to be performed by Landlord
                  hereunder.

                           e. At Tenant's request, Landlord will require any
                  janitorial service or prospective tenant for the Building or
                  proposed purchaser of the Building to execute a reasonable
                  confidentiality agreement agreeing not to disclose to any
                  third party trade secrets or intellectual property of Tenant
                  or medical information of patients obtained by means of
                  access to the Premises.

MISCELLANEOUS     24.      a. LANDLORD TRANSFER.  Landlord may transfer, in 
                  whole or in part, the Building and any of its rights under
                  this Lease. If Landlord assigns its rights under this Lease,
                  then Landlord shall thereby be released from any further
                  obligations hereunder occurring after the date of such
                  transfer, provided that the assignee assumes Landlord's
                  obligations hereunder occurring after the date of such
                  transfer in writing except that such assignee shall not be
                  bound by, or assume any liability with respect to, (a) any
                  payment of Rent for more than one month in advance (except
                  prepayments for security deposits, if any), (b) any
                  amendments or modifications of this Lease made without the
                  prior written consent of Landlord's Mortgagee if Tenant was
                  advised on the interest of the same, or (c) any credits,
                  offsets, defenses or claims which Tenant may have against
                  Landlord.





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                           b. LANDLORD'S DEFAULT AND LIABILITY. If Landlord
                  fails to perform any of its obligations under this Lease,
                  Landlord shall not be in default hereunder and Tenant shall
                  not have any rights or remedies growing out of such failure
                  unless Tenant gives Landlord written notice thereof setting
                  forth in reasonable detail the nature and extent of such
                  failure and such failure by Landlord is not cured within a
                  thirty (30) day period following delivery of such notice or
                  such longer period provided elsewhere in this Lease. If such
                  failure cannot reasonably be cured within such thirty (30)
                  day period, the length of such period shall be extended for
                  the period reasonably required therefore if Landlord
                  commences curing such failure within such thirty (30) day
                  period and continues to take action to cure such failure with
                  reasonable diligence and continuity. The liability of
                  Landlord to Tenant for any default by Landlord under the
                  terms of this Lease shall be limited to Tenant's actual
                  direct, but not consequential, damages therefor and shall be
                  recoverable only from the interest of Landlord in the
                  Building and the Land, and Landlord shall not be personally
                  liable for any deficiency.

                           c. FORCE MAJEURE. Other than for Tenant's monetary
                  obligations under this Lease, whenever a period of time is
                  herein prescribed for action to be taken by either party
                  hereto, such party shall not be liable or responsible for,
                  and there shall be excluded from the computation for any such
                  period of time, any delays due to strikes, riots, acts of
                  God, shortages of labor or materials, war, governmental laws,
                  regulations, or restrictions, or any other causes of any kind
                  whatsoever which are beyond the control of such party. Any
                  elimination or shutting off of light, air, or view by any
                  structure which may be erected on lands adjacent to the
                  Building shall in no way affect this Lease or impose any
                  liability on Landlord.

                           d. CRIMINAL ACTS OF THIRD PARTIES. Any security
                  guards or security services provided by Landlord for the
                  Building, Appurtenant Facilities or Land are provided for the
                  protection of Landlord's property. Tenant shall be
                  responsible for the protection of Tenant and Tenant's
                  employees, agents, contractors, invitees and licensees and
                  their property against criminal acts of third parties.
                  Landlord shall not be liable to Tenant or any other party for
                  criminal acts of third parties whether or not such acts are
                  foreseeable. Tenant shall contact the local police and rely
                  on the local police for protection against criminal acts.

                           e. BROKERAGE. Landlord and Tenant each warrant to
                  the other that it has not dealt with any broker or agent in
                  connection with the negotiation or execution of this Lease
                  other than the Broker (if any) and Landlord's property
                  manager. Tenant and Landlord shall each indemnify the other
                  against all costs, expenses, attorneys' fees, and other
                  liability for commissions or other compensation claimed by
                  any broker or agent other than the Broker (if any) and the
                  property manager claiming the same by, through, or under the
                  indemnifying party.










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                           f. ESTOPPEL CERTIFICATES. From time to time, Tenant
                  shall furnish to any party designated by Landlord, within ten
                  (10) days after Landlord has made a request therefor, a
                  certificate signed by Tenant confirming and containing such
                  factual certifications and representations as to this Lease
                  as Landlord may reasonably request.

                           g. NOTICES. All notices and other communications
                  given pursuant to this Lease shall be in writing and shall be
                  (i) mailed by first class, United States Mail (or Canada
                  Mail, as appropriate), postage prepaid, certified, with
                  return receipt requested, and addressed to the parties hereto
                  at the address specified in the Basic Lease information, (ii)
                  hand delivered to the intended address, or (iii) sent by
                  prepaid telegram, cable, facsimile transmission, or telex
                  followed by a confirmatory letter. Notice sent by certified
                  mail, postage prepaid, shall be effective three (3) business
                  days after being deposited in the United States mail (or
                  Canada Mail, as appropriate); all other notices shall be
                  effective upon delivery to the address of the addressee. The
                  parties hereto may change their addresses by giving notice
                  thereof to the other in conformity with this provision.

                           h. SEVERABILITY. If any clause or provision of this
                  Lease is illegal, invalid, or unenforceable under present or
                  future laws, then the remainder of this Lease shall not be
                  affected thereby and in lieu of such clause or provision,
                  there shall be added as a part of this Lease a clause or
                  provision as similar in terms to such illegal, invalid, or
                  unenforceable clause or provision as may be possible and be
                  legal, valid, and enforceable.

                           i. AMENDMENTS; AND BINDING EFFECT. This Lease
                  (including all Exhibits hereto) constitutes the entire
                  agreement between Landlord and Tenant and supersedes all
                  prior discussions and agreements of the parties relating to
                  the Premises and the Building. This Lease may not be amended
                  except by instrument in writing signed by Landlord and
                  Tenant. Whenever any approval or consent of the Landlord is
                  required, such approval or consent shall not be binding on
                  Landlord unless expressed in writing and executed by an
                  authorized representative of Landlord. No provision of this
                  Lease shall be deemed to have been waived by Landlord unless
                  such waiver is in writing signed by Landlord, and no custom
                  or practice which may evolve between the parties in the
                  administration of the terms hereof shall waive or diminish
                  the right of Landlord to insist upon the performance by
                  Tenant in strict accordance with the terms hereof. The terms
                  and conditions contained in this Lease shall inure to the
                  benefit of and be binding upon the parties hereto, and upon
                  their respective successors in interest and legal
                  representatives, except as otherwise herein expressly
                  provided. This Lease is for the sole benefit of Landlord and
                  Tenant, and, other than Landlord's Mortgagee, no third party
                  shall be deemed a third party beneficiary hereof.

                           j. QUIET ENJOYMENT. Provided Tenant has performed
                  all of the terms and conditions of this Lease to be performed
                  by Tenant, Tenant shall peaceably and quietly hold and enjoy
                  the Premises for the Term, without hindrance from Landlord or
                  any party claiming by, through, or under Landlord, subject to
                  the terms and conditions of this Lease.









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                           k. JOINT AND SEVERAL LIABILITY. If there is more
                  than one Tenant, then the obligations hereunder imposed upon
                  Tenant shall be joint and several. If there is a guarantor of
                  Tenant's obligations hereunder, then the obligations
                  hereunder imposed upon Tenant shall be the joint and several
                  obligations of Tenant and such guarantor, and Landlord need
                  not first proceed against Tenant before proceeding against
                  such guarantor nor shall any such guarantor be released from
                  its guaranty for any reason whatsoever.

                           l. CAPTIONS.  The captions contained in this Lease 
                  are for convenience of reference only, and do not limit or
                  enlarge the terms and conditions of this Lease.

                           m. NO MERGER. There shall be no merger of the
                  leasehold estate hereby created with the fee estate in the
                  Premises or any part thereof if the same person acquires or
                  holds, directly or indirectly, this Lease or any interest in
                  this Lease and the fee estate in the leasehold Premises or
                  any interest in such fee estate.

                           n. NO OFFER.  The submission of this Lease to Tenant
                  shall not be construed as an offer, nor shall Tenant have any
                  rights under this Lease unless Landlord executes a copy of
                  this Lease and delivers it to Tenant.

                           o. NO RIGHTS TO USE OF BUILDING NAME. Tenant shall
                  have no interest in, or rights to, the name of the Building.
                  Landlord will have the right, exercisable upon written notice
                  and without liability to any tenant, to change the name and
                  street address of the Building. Tenant shall not engage in
                  any advertising mentioning the Building without the prior
                  written consent of Landlord. Landlord shall have the right to
                  prohibit any advertising by Tenant mentioning the Building
                  that, in Landlord's opinion, tends to impair the reputation
                  of the Building or its desirability as a building for
                  offices, and upon written notice from Landlord, Tenant will
                  refrain from or discontinue such advertising. Tenant has the
                  option to use or refrain from using the name of the Building
                  on its stationery.

                           p. TIME OF ESSENCE. Except as provided in Section
                  24c. hereof, time is of the essence of this Lease and each
                  and all of its provisions in which performance is a factor.

                           q. AUTHORITY OF PARTIES. If Tenant is a corporation,
                  limited partnership, partnership, trust or other entity, each
                  person executing this Lease on behalf of said entity
                  represents and warrants to Landlord that such person is duly
                  authorized to execute and deliver this Lease on behalf of
                  said entity and that this Lease is binding upon said entity
                  in accordance with its terms.

                           r. GOVERNING LAW.  This Lease shall be governed by
                  the laws of the state in which the Premises are located.










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                           s. EXHIBITS.  All exhibits and attachments attached
                  hereto are incorporated herein by this reference.

                          Exhibit A - Outline of Premises
                          Exhibit B - Building Rules and Regulations
                          Exhibit C - Workletter for Suite #300
                          Exhibit D - Parking Agreement
                          Exhibit E - Workletter for Suite #170

SPECIAL 
PROVISIONS        25.   a.RENEWAL OPTION:  Tenant has two (2) option(s) (as to 
                  each, an "Option") to renew and extend the Term of this Lease
                  for sixty (60) months each (the "Renewal Term"), which
                  Option(s) shall follow consecutively on the expiration of the
                  Term (or Renewal Term, as appropriate,) of this Lease,
                  provided that at the time that the Option to renew is
                  exercised, this Lease is in full force and effect, Tenant has
                  not vacated the Premises, and Tenant is not in default
                  hereunder. The Option shall be exercised by Tenant's giving
                  to Landlord written notice of its intention to renew and
                  extend the Term of this Lease at least six (6) months before
                  the expiration date of the initial Term (or Renewal Term, as
                  appropriate,) of this Lease. The renewal and extension of
                  this Lease for the Renewal Term shall be on and under the
                  same covenants, agreements, terms, provisions, and conditions
                  as are contained herein for the initial Term of this Lease,
                  including those providing for adjustments to the rent;
                  provided, however, that the Leasehold Improvements to be
                  provided by Landlord for the Renewal Term will be sufficient
                  to cover the costs of repainting and recarpeting the Premises
                  and provided, further, that the rent for the Renewal Term
                  shall be established as follows: on or before nine (9) months
                  prior to the expiration date of the initial Term (or Renewal
                  Term as appropriate) of this Lease, Tenant shall give
                  Landlord written notice of its preliminary intention to renew
                  and extend the Term of this Lease. The parties shall attempt
                  to reach agreement on the rental, which is to be 95% of the
                  market rental for new leases in comparable buildings in the
                  I-10 corridor in suburban San Antonio, Texas for the Renewal
                  Term for which the option is being exercised (the "Renewal
                  Rental"). If the parties agree on the Renewal Rental, Tenant
                  must give written notice of the exercise of its right to
                  renew the Term of this Lease on or before six months prior to
                  the expiration of the prior Term or Renewal Term as
                  applicable. If the parties are unable to reach agreement as
                  to the rental for the applicable Renewal Term within thirty
                  (30) days after Tenant's preliminary notice of its intention
                  to renew the Term of the Lease, each party shall appoint and
                  pay the fees and expense for the services of a licensed real
                  estate broker who specializes in office leasing in the San
                  Antonio, Texas market of buildings of comparable type, size
                  and quality and who has at least two (2) years of experience
                  in the local market. The two (2) brokers selected shall
                  attempt to reach agreement acceptable to Landlord and Tenant
                  as to an amount equal to 95% of the market rental for the
                  space taking into account leases in buildings of comparable
                  type, size and quality including leases made within the
                  Building within the prior year. Should such leasing agents
                  fail to reach agreement, the parties shall have the option of
                  attempting to mediate the dispute. In the event of the
                  exercise of renewal option, the Base Year for purposes of
                  determining the amount of Operating Expense Reimbursement
                  shall be adjusted to be the first year of the Renewal Term
                  for which the option is then being exercised Any assignment
                  or subletting by Tenant in violation or breach of Section 10
                  of this Lease shall terminate the Option(s) of Tenant set
                  forth herein.

                  Any termination of this Lease during the initial Term or
                  Renewal Term shall terminate any further rights of renewal
                  and extension set forth in this provision.




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                  At any time during the forty-five (45)-day period immediately
                  preceding the date by which Tenant is required to exercise a
                  renewal Option, Tenant may request in writing a quote from
                  Landlord of the rent that will be applicable for the next
                  Renewal Term. Landlord shall respond to a timely written
                  request by providing Tenant a written quote of the rent
                  within five (5) business days after Landlord's receipt of
                  Tenant's request.

                       b.  NON-DISTURBANCE:  Landlord shall provide
                  non-disturbance and attornment agreements from all current
                  lenders and will work in good faith to provide such
                  agreements from any future lenders, all of such agreements to
                  be in form reasonably satisfactory to Tenant and the lender
                  in question. .

                       c. EXPANSION SPACE: Tenant shall have the option to
                  lease additional office space (the "First Expansion Option")
                  containing approximately 11,090 RSF on the first (1st) floor
                  of the Building (the "First Expansion Space") as more
                  particularly depicted on Exhibit "A" attached hereto as of
                  July 1, 1998. To exercise the First Expansion Option Tenant
                  shall give written notice to Landlord by December 31, 1997
                  and within seven (7) days of Landlord's delivery of an
                  amendment to the Lease documenting the leasing of the First
                  Expansion Space, Tenant shall return same fully executed to
                  Landlord. Such First Expansion Option shall provide Tenant
                  with the ability to lease all or a part of this area at
                  Tenant's sole discretion, but in no event less than 5,000 RSF
                  and subject to fire and Building code restrictions and so
                  long as the remaining space not leased by Tenant under this
                  option is left in a relettable condition, in Landlord's
                  reasonable discretion.

                  Tenant shall have the option to lease additional office space
                  (the "Second Expansion Option") out of the area of the
                  Building containing approximately 18,937 RSF on the second
                  (2nd) floor of the Building (the "Second Expansion Space") as
                  more particularly depicted on Exhibit "A" attached hereto as
                  of October 1, 1998. The Second Expansion Option shall only be
                  effective in the event the tenant currently occupying the
                  Second Expansion Space as of the date of this Lease (E-Med)
                  its affiliates, subsidiaries or successor in interest,
                  vacates or reduces the office space it presently occupies. In
                  the event said space is made available at that time, Tenant
                  may exercise the Second Expansion Option by providing written
                  notice to Landlord by March 31, 1998 and within seven (7)
                  days of Landlord's delivery of an amendment to the Lease
                  documenting the leasing of the Second Expansion Space, Tenant
                  shall return same fully executed. Such Second Expansion
                  Option shall provide Tenant with the ability to lease this
                  entire area at Tenant's sole discretion, but in no event less
                  than 3,000 RSF and subject to fire and Building code
                  restrictions and so long as the remaining space not leased by
                  Tenant under this option is left in a relettable
                  configuration, in Landlord's reasonable discretion. Landlord
                  shall deliver said amendment to Lease to Tenant for execution
                  only in the event such Second Expansion Space becomes
                  available. In the event Second Expansion Space does not
                  become available, Landlord shall inform Tenant within ten
                  (10) days of such event, and shall agree









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                  to work in good faith with Tenant to find additional office
                  space elsewhere in the Building to meet Tenant's space
                  requirements.

                  Landlord shall not be liable for any damages resulting from
                  the unauthorized holding over of any existing tenant of
                  either such expansion space and any such spaces leased shall
                  be leased at the market rate for new leases in comparable
                  buildings. All expansion space shall be leased with
                  additional surface parking in a ratio of one (1) space for
                  every additional 300 RSF leased.

                  If Tenant exercises an option or options to lease additional
                  office space as provided in this paragraph: (i) Tenants
                  Proportionate Share will be adjusted to reflect the
                  additional space being leased by Tenant (ii) the lease terms
                  for the additional space will be coterminous with the Term of
                  this Lease (iii) the Leasehold Improvements allowance of
                  $9.94 per square foot will be adjusted to reflect the shorter
                  lease term for the additional space and (iv) the Basic Rental
                  for the additional space will be 95% of the market rental for
                  new leases in comparable buildings in the I-10 corridor in
                  San Antonio, Texas for comparable lease terms.

                       d. NOTICE OF AVAILABILITY. Landlord shall provide Tenant
                  with a Notice of Availability indicating the RSF of each
                  space in the Building (other than the expansion spaces) as
                  they become available for leasing, provided no other tenant
                  has a preferential right to lease such space. The purpose of
                  this Notice of Availability is to merely provide Tenant with
                  a means to plan for Tenant's anticipated office space needs
                  and shall in no way be deemed to provide Tenant a right of
                  first refusal to lease any such areas and Landlord shall at
                  all times retain the right to enter into a lease with any
                  tenant for any such space.

                       e. EXTERIOR SIGNAGE: Tenant shall have the right, at its
                  sole cost and expense, to install exterior signage on the
                  Building in the approximate location formerly occupied by
                  Datarace, Inc.. Landlord shall have the right to approve all
                  aspects of such signage to include, but not be limited to,
                  specific location, size, materials, orientation, color, style
                  and method of installation. Tenant shall also have the
                  obligation to maintain said signage throughout the Term of
                  the Lease in a manner acceptable to Landlord. Tenant shall
                  remove such signage and return the site to its original
                  condition at Tenant's sole cost and expense within fourteen
                  (14) days of Tenant's vacating of the Premises.

                       f. TEMPORARY PREMISES: Effective upon the full execution
                  of this Lease, Tenant shall have the right to use and occupy
                  approximately 3,250 RSF of the Premises (the "Temporary
                  Premises") on the third (3rd) floor of the Building in the
                  location indicated on Exhibit "A" until the Commencement Date
                  referenced in Section 3 of the Lease. All of the provisions
                  of this Lease shall be in full force and effect, except that
                  the Temporary Premises shall be leased on a rent free basis
                  and the Term of the Lease shall be extended to include the
                  number of days Tenant uses and occupies the Temporary
                  Premises prior to the Commencement Date. Landlord shall have
                  no obligation to make any repairs or perform any improvements
                  in the Temporary Premises prior to Tenant's occupancy of the
                  same, provided however, Landlord shall re-key the Temporary
                  Premises, clean the Temporary Premises, replace missing
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                  throughout the Temporary Premises and ensure that all lights
                  are in working order. To enable Landlord's contractor to
                  complete construction in that portion of the Premises
                  identified as the Temporary Premises on Exhibit "A" attached
                  hereto, Tenant shall have the option of relocating, at
                  Tenant's sole cost and expense, the Temporary Premises during
                  Landlord's construction and prior to the Commencement Date to
                  another portion of the Premises (to be identified on Tenant's
                  Final Plans) where Landlord's contractor will have
                  substantially completed the work outlined in Exhibit "C"
                  attached hereto (in which case Basic Rental for the Temporary
                  Premises shall remain rent free), or waiting until the
                  Premises is substantially complete except for the area
                  covered by the Temporary Premises (in which case the Basic
                  Rental for the entire Premises shall commence unabated). The
                  parties agree to cooperate to avoid invalidation of the
                  contractor's or Landlord's insurance by reason of such
                  occupancy.




                  EXECUTED effective as of the Lease Date set forth in the
Basic Lease Information.

                                  LANDLORD:

DATE OF EXECUTION:                N.W.A. LIMITED PARTNERSHIP

                                  BY: 
                                      -------------------------------------
                                           IRIS S. STEWART
                                           VICE PRESIDENT OF ITS
                                           GENERAL PARTNER
                                           GEORGE INVESTMENT GROUP, INC.


                                  TENANT:

DATE OF EXECUTION:                ILEX ONCOLOGY, INC., A DELAWARE CORPORATION.

                                  BY: 
                                      -------------------------------------


                                      -------------------------------------
                                           Printed Name

                                      -------------------------------------
                                           Title











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