<PAGE>
                                                                   EXHIBIT 10.20

 
                                 OFFICE LEASE


                                by and between


                          SEOC I LIMITED PARTNERSHIP,
                        an Arizona limited partnership,

                                  "LANDLORD"

                                      and

                            CBT SYSTEMS USA, LTD.,
                            a Delaware corporation
                                   "TENANT"



                              December 31, 1997



                            EXECUTIVE OFFICE CENTER

                              Scottsdale Airpark
                       16100 North Greenway/Hayden Loop
                           Scottsdale, Arizona 85260

<PAGE>
 
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                               TABLE OF CONTENTS
                               -----------------

                                                                      Page
                                                                      ----
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1.   BASIC PROVISIONS................................................   1
2.   LEASED PREMISES; NO ADJUSTMENTS.................................   2
3.   LEASE TERM; COMMENCEMENT DATE...................................   3
4.   SECURITY DEPOSIT................................................   3
5.   RENT; RENT TAX; ADDITIONAL RENT.................................   4
6.   OPERATING COSTS.................................................   4
7.   CONDITION, REPAIRS AND ALTERATIONS..............................   7
8.   SERVICES........................................................   8
9.   LIABILITY AND PROPERTY INSURANCE................................   9
10.  RECONSTRUCTION..................................................  11
11.  WAIVER OF SUBROGATION...........................................  12
12.  LANDLORD'S RIGHT TO PERFORM TENANT OBLIGATIONS..................  13
13.  DEFAULT AND REMEDIES............................................  13
14.  LATE PAYMENTS...................................................  15
15.  ABANDONMENT AND SURRENDER.......................................  15
16.  INDEMNIFICATION AND EXCULPATION.................................  15
17.  ENTRY BY LANDLORD...............................................  16
18.  RESERVED........................................................  17
19.  ASSIGNMENT AND SUBLETTING.......................................  17
20.  USE OF LEASED PREMISES AND RUBBISH REMOVAL......................  18
21.  SUBORDINATION AND ATTORNMENT....................................  19
22.  ESTOPPEL CERTIFICATE............................................  20
23.  SIGNS...........................................................  20
24.  PARKING.........................................................  20
25.  LIENS...........................................................  21
26.  HOLDING OVER....................................................  21
27.  ATTORNEYS' FEES.................................................  21
28.  RESERVED RIGHTS OF LANDLORD.....................................  21
29.  EMINENT DOMAIN..................................................  22
30.  NOTICES.........................................................  23
31.  RULES AND REGULATIONS...........................................  23
32.  ACCORD AND SATISFACTION.........................................  23
33.  BANKRUPTCY OF TENANT............................................  23
34.  HAZARDOUS MATERIALS.............................................  25
35.  MISCELLANEOUS...................................................  27
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                                       i
<PAGE>

 
                                 OFFICE LEASE

                              1.  BASIC PROVISIONS
                                  ----------------
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<S>                                            <C>                      
1.1             Date:                           December 31, 1997                                    
                ----                                     --                                         
                                                                                                    
1.2             Landlord:                       SEOC I Limited Partnership, an Arizona limited      
                --------                        partnership                                         
                                                                                                    
                                                                                                    
1.3             Landlord's Address:             c/o Cavan Investments, Ltd.                         
                -------------------             15880 North Greenway/Hayden Loop, Suite 700
                                                Phoenix, Arizona 85260                              
                                                Attention:  Mr. Steven E. Barger                    
                                                
                                                                                                    
1.4             Tenant:                         CBT Systems USA, Ltd., a Delaware corporation        
                ------

1.5             Tenant's Address:
                ---------------- 

                (a)  Prior to Commencement
                     ---------------------
                     Date:                      1005 Hamilton Court
                     ----                       Menlo Park, California 94025                    
                                                Attention:  CFO and General Counsel 
                                                

                (b)  Subsequent to
                     -------------
                     Commencement Date:         To the address set forth in Section 1.5(a) and to:
                     -----------------                                      --------------    
                                                16100 North Greenway-Hayden Loop
                                                Suite 800 (Building E)
                                                Scottsdale, Arizona 85260
                                                Attention:  General Manager

1.6             Project:                        The parcel of real estate commonly known as Executive Office
                -------                         Center, located in Scottsdale, Maricopa County,   
                                                Arizona, legally described on Exhibit "A"              
                                                                              -----------              
                                                attached hereto and incorporated herein by this        
                                                reference, together with the office buildings          
                                                now or hereafter situated thereon, the                 
                                                landscaping, parking facilities and all other          
                                                improvements and appurtenances thereto.                 
                                                

1.7             Building:                       That certain office building known as Executive
                --------                        Office Center located at 16100 North Greenway-           
                                                Hayden Loop, Scottsdale Airpark, Scottsdale,       
                                                Maricopa County, Arizona 85260, and situated on    
                                                the Project.                                        
                                                

1.8             Leased Premises:                25,571 rentable square feet of office space commonly
                ---------------                 known as Suite 800 (Building E), as outlined on  
                                                the Floor Plan attached hereto as Exhibit "B".          
                                                
 
 
1.9             Permitted Use:                  General office, warehousing, research and
                -------------                   development, shipping, receiving, and storage. 
                                                
 
1.10            Lease Term:                     5 years and 1 month.
                ----------
 
1.11            Scheduled Commencement Date
                ---------------------------
                and Expiration Date:            April 1, 1998 and April 30, 2003.
                -------------------
 
1.12            Annual Basic Rent:              LEASE MONTH 1:  No charge for Basic Rent.
                -----------------
                                                LEASE MONTHS 2-37: $30,898.29 per month based         
                                                upon a rental rate of $14.50 per rentable square foot. 
                                                
                                                LEASE MONTHS 38-61:  $32,496.48 per month based             
                                                upon a rental rate of $15.25 per rentable square foot. 
 

1.13            Security Deposit:               $30,898.29                                   
                ----------------
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1.14            Building Hours:                   7:00 a.m. to 6:00 p.m., Monday through Friday, and
                --------------                    8:00 a.m. to 12:00 p.m. on Saturday,
                                                  excluding recognized federal, state and local holidays.
                                                  
 
1.15            Parking Spaces:                   152 parking spaces, of which, at Tenant's election, up
                --------------                    to 25 are covered reserved and the balance are uncovered unreserved, 
                                                  increased to 203 total spaces if the premises currently occupied by 
                                                  the Mayo Clinic is vacated, and increased pro rata if Tenant leases 
                                                  additional premises in the Project. Tenant shall make its election  
                                                  to use the covered reserved parking spaces by executing the Parking 
                                                  License in the form of Exhibit "D" attached hereto.                  
                                                                         ----------
 
1.16            Parking Charge:                   $25.00 per covered reserved space per month.
                --------------
 
1.17            Guarantors:                       None.
                ----------
 
1.18            Broker:                           Lee & Associates and CB Commercial.
                ------
 
1.19            Exhibits:                         A = Legal Description of the Project
                --------                          B = Floor Plan                      
                                                  C = Memorandum of Commencement Date 
                                                  D = Reserved Covered Parking License
                                                  E = Reserved.                       
                                                  F = Unreserved Parking License      
                                                  G = Work Letter                     
                                                  H = Building Rules and Regulations  
                                                  I = Loading Zone Site Plan          
                                                  
 
1.20           Loading Zone:                      2 parking spaces designated as loading zone and
               ------------                       depicted on the loading zone exhibit attached hereto 
                                                  as Exhibit "I".                                     
                                                     -----------                                       
                                                  
 
1.21            Riders:                           1 = Option to Extend
                ------                                                             
                                                  2 = Right of First Refusal
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                      2.  LEASED PREMISES; NO ADJUSTMENTS
                          -------------------------------

     2.1  Leased Premises.  Landlord hereby leases to Tenant, and Tenant hereby
          ---------------                                                      
leases and accepts from Landlord, the Leased Premises, upon the terms and
conditions set forth in this Lease and any modifications, supplements or addenda
hereto (the "Lease"), including the Basic Provisions of Article 1 which are
             -----                                      ---------          
incorporated herein by this reference, together with the nonexclusive right to
use, in common with Landlord and others, the Building Common Areas (defined
below) and the Project Common Areas (defined below).  For the purposes of this
Lease, the term "Building Common Areas" means common hallways, corridors,
                 ---------------------                                   
walkways and footpaths, foyers and lobbies, bathrooms and janitorial closets,
electrical and telephone closets, landscaped areas, and such other areas within
or adjacent to the Building which are subject to or are designed or intended
solely for the common enjoyment, use and/or benefit of the tenants of the
Building.  The term "Project Common Areas" means common walkways, footpaths,
                     --------------------                                   
driveways, parking areas, service areas, landscaped areas, and such other areas
within or adjacent to the Project which are subject to or are designed or
intended solely for the common enjoyment, use and/or benefit of the tenants of
the Project.  The Building Common Areas and Project Common Areas shall consist
of at least those areas that are currently designated as such by Landlord.
Tenant shall have the nonexclusive right to use those spaces depicted on the
Loading Zone Site Plan attached hereto as Exhibit "I".
                                          ----------- 

     2.2  Adjustments.  The Annual Basic Rent at the Commencement Date (as
          -----------                                                     
hereinafter defined) is based on the Leased Premises containing the rentable
square footage set forth in Article 1.8 above.  If the actual rentable square
                            -----------                                      
footage of the Leased Premises is more or less than the square footage set forth
in Article 1.8 above (to be computed in accordance with BOMA standards after
   -----------                                                              
completion of the Leased Premises, by McCarthy Nordberg), the Annual Basic Rent
shall be increased or decreased in accordance with the rental rate set forth in
                                                                               
Article 1.12 above.
------------       

                                       2
<PAGE>
 
                       3.  LEASE TERM; COMMENCEMENT DATE
                           -----------------------------

     3.1  Lease Term.  The Lease Term shall begin on the Commencement Date and
          ----------                                                          
shall be for the period set forth in Article 1.10 above, plus any period of less
                                     ------------                               
than one (1) month between the Commencement Date and the first day of the next
succeeding calendar month, unless sooner terminated in accordance with the
further provisions of this Lease.

     3.2  Commencement Date.  The Commencement Date shall mean the date by which
          -----------------                                                     
(a) Landlord has Substantially Completed the Tenant Improvements (as defined in
Exhibit "G") in accordance with this Lease, (b) Landlord has delivered
-----------                                                           
possession of the Leased Premises to Tenant in the condition required herein,
and (c) Tenant has had a period of not less than seven (7) business days to
install its fixtures, furniture and equipment.  The Expiration Date shall be
adjusted based on the actual Commencement Date.

     3.3  Memorandum of Commencement Date.  Landlord and Tenant shall, within
          -------------------------------                                    
ten (10) days after the Commencement Date, execute a declaration in the form of
Exhibit "C" attached hereto specifying the Commencement Date should the
-----------                                                            
Commencement Date be a date  other than the Scheduled Commencement Date.

     3.4  Delay in Commencement Date.  In the event Landlord shall be unable,
          --------------------------                                         
for any reason, to deliver possession of the Leased Premises to Tenant on the
Scheduled Commencement Date, Landlord shall not be liable for any loss or damage
occasioned thereby, nor shall such inability affect the validity of this Lease
or the obligations of Tenant.  In such event, Tenant shall not be obligated to
pay Annual Basic Rent or Additional Rent or perform any other obligations
hereunder until the Commencement Date.  In the event the Commencement Date has
not occurred for any reason within thirty (30) days after the Scheduled
Commencement Date, other than due to Tenant Delays, then, in addition to
Tenant's other rights or remedies, the date Tenant is otherwise obligated to
commence payment of Rent shall be delayed by one day for each day that the
Commencement Date is delayed beyond such date, or, at Tenant's election, Tenant
shall have the right to terminate this Lease by delivering written notice of
termination to Landlord at any time within thirty (30) days after the expiration
of such thirty (30) day period.  Such termination shall be effective thirty (30)
days after receipt by Landlord of Tenant's notice of termination.  Upon a
termination of this Lease pursuant to the provisions of this Article 3.4, the
                                                             -----------     
parties shall have no further obligations or liabilities to the other and
Landlord shall promptly return any monies previously deposited or paid by
Tenant.

     3.5  Lease Year.  Each "Lease Year" shall be a period of twelve (12)
          ----------         ----------                                  
consecutive calendar months, the first Lease Year beginning on the Commencement
Date or on the first day of the calendar month next succeeding the Commencement
Date if the Commencement Date is not on the first day of a calendar month. Each
Lease Year after the first Lease Year shall begin on the calendar day next
succeeding the expiration of the immediately preceding Lease Year.

                              4.  SECURITY DEPOSIT
                                  ----------------

     Tenant shall pay to Landlord, upon the execution of this Lease, the
Security Deposit set forth in Article 1.13 above as security for the performance
                              ------------                                      
by Tenant of its obligations under this Lease, which amount shall be returned to
Tenant after the expiration or earlier termination of this Lease, provided that
Tenant shall have fully performed all of its obligations contained in this
Lease.  The Security Deposit, at the election of Landlord, may be retained by
Landlord as and for its full damages or may be applied in reduction of any loss
and/or damage sustained by Landlord by reason of the occurrence of any Event of
Default by Tenant under this Lease without the waiver of any other right or
remedy available to Landlord at law, in equity or under the terms of this Lease.
If any portion of the Security Deposit is so used or applied, Tenant shall,
within five (5) days after written notice from Landlord, deposit with Landlord
immediately available funds in an amount sufficient to restore the Security
Deposit to its original amount, and Tenant's failure to do so shall be a breach
of this Lease.  Tenant acknowledges and agrees that in the event Tenant shall
file a voluntary petition pursuant to the Bankruptcy Code or any successor
thereto, or if an involuntary petition is filed against Tenant pursuant to the
Bankruptcy Code or any successor thereto and such involuntary petition is not
dismissed within sixty (60) days, then Landlord may apply the Security Deposit
towards those obligations of Tenant to Landlord which accrued prior to the
filing of such petition.  Tenant acknowledges further that the Security Deposit
may be commingled with Landlord's other funds and that Landlord shall be
entitled to retain any interest earnings thereon.  In the event of termination
of Landlord's interest in this Lease, Landlord shall transfer the Security
Deposit to Landlord's successor in interest, whereupon Landlord shall be
released from liability by Tenant for the return of such deposit or the
accounting therefore.

                                       3
<PAGE>
 
                      5.  RENT; RENT TAX; ADDITIONAL RENT
                          -------------------------------

     5.1  Payment of Rent.  Tenant shall pay to Landlord the Annual Basic Rent
          ---------------                                                     
set forth in Article 1.12 above, subject to adjustment as provided herein.  The
             ------------                                                      
Annual Basic Rent shall be paid in equal monthly installments, on or before the
first day of each and every calendar month during the Lease Term, in advance,
without notice or demand and without abatement, deduction or offset, except as
otherwise set forth herein.  If the Commencement Date is other than the first
day of a calendar month, the payment for the partial month following the
Commencement Date shall be prorated and shall be payable on the first day of the
first full calendar month of the Lease Term.  The Annual Basic Rent for the
first full month of the Lease Term shall be paid upon the execution of this
Lease.  All payments requiring proration shall be prorated on the basis of a
thirty (30) day month.  In addition, all payments to be made under this Lease
shall be paid in lawful money of the United States of America to Landlord or its
agent at the address set forth in Article 1.3 above, or to such other person or
                                  -----------                                  
at such other place as Landlord may from time to time designate in writing.

     5.2  Rent Tax.  In addition to the Annual Basic Rent and Additional Rent,
          --------                                                            
Tenant shall pay to Landlord, together with the monthly installments of Annual
Basic Rent and payments of Additional Rent, an amount equal to any governmental
taxes, including, without limitation, any sales, rental, occupancy, excise, use
or transactional privilege taxes assessed or levied upon Landlord with respect
to the amounts paid by Tenant to Landlord hereunder, as well as all taxes
assessed or imposed upon Landlord's gross receipts or gross income from leasing
the Leased Premises to Tenant, including, without limitation, transaction
privilege taxes, education excise taxes, any tax now or hereafter imposed by the
City of Scottsdale, the State of Arizona, any other governmental body, and any
taxes assessed or imposed in lieu of or in substitution of any of the foregoing
taxes.  Such taxes shall not, however, include any franchise, gift, estate,
inheritance, conveyance, transfer or net income tax assessed against Landlord.

     5.3  Additional Rent.  In addition to Annual Basic Rent, all other amounts
          ---------------                                                      
to be paid by Tenant to Landlord pursuant to this Lease (including amounts to be
paid by Tenant pursuant to Article 6 below and parking charges to be paid by
                           ---------                                        
Tenant pursuant to Exhibits "D" and "F"), if any, shall be deemed to be
                   --------------------                                
Additional Rent, whether or not designated as such, and shall be due and payable
within thirty (30) days after receipt by Tenant of Landlord's statement.
Landlord shall have the same remedies for the failure to pay Additional Rent as
for the nonpayment of Annual Basic Rent.

                              6.  OPERATING COSTS
                                  ---------------

     6.1  Tenant's Obligation.  The Annual Basic Rent does not include amounts
          -------------------                                                 
attributable to Taxes (defined below) or amounts attributable to the cost of the
use, management, repair, service, insurance, condition, operation and
maintenance of the Building and the Project.  Therefore, in order that the
Annual Basic Rent payable throughout the Lease Term shall reflect such amounts,
Tenant shall pay to Landlord, in accordance with the further provisions of this
Article 6, an amount equal to the Operating Costs (as hereinafter defined) per
---------                                                                     
rentable square foot of the Leased Premises.

     6.2  Landlord's Estimate.  Landlord shall furnish Tenant an estimate of the
          -------------------                                                   
Operating Costs per rentable square foot for each calendar year.  In addition,
Landlord may, from time to time, but no more than twice per year, furnish Tenant
a  revised estimate of Operating Costs should Landlord anticipate any increase
in Operating Costs from that set forth in a prior estimate.  Commencing with the
first month to which an estimate applies, Tenant shall pay, in addition to the
monthly installments of Annual Basic Rent, an amount equal to one-twelfth
(1/12th) of the Operating Expenses per rentable square foot of the Leased
Premises; provided, however, if less than ninety-five percent (95%) of the
rentable area of the Building shall be occupied by tenants during the period
covered by such estimate, the estimated Operating Costs for such period shall
be, for the purposes of this Article 6, increased to an amount reasonably
                             ---------                                   
determined by Landlord to be equivalent to the Operating Costs that would be
incurred if occupancy would be at least ninety-five percent (95%) during the
entire period.  Within one hundred twenty (120) days after the expiration of
each calendar year or such longer period of time as may be necessary to compile
such statement, but in no event longer than one hundred eighty (180) days from
the beginning of the calendar year, Landlord shall deliver to Tenant a
reasonably detailed and itemized statement of the actual Operating Costs for
such calendar year.  If the actual Operating Costs for such calendar year are
more or less than the estimated Operating Costs, a proper adjustment shall be
made; provided, however, if less than ninety-five percent (95%) of the rentable
area of the Building shall have been occupied by tenants at any time during such
period, the actual Operating Costs for such period shall be, for the purposes of
this Article 6, increased to an amount reasonably determined by Landlord to be
     ---------                                                                
equivalent to the Operating Costs that would have been incurred had such
occupancy been at least ninety-five (95%) during the entire period.  Any excess

                                       4
<PAGE>
 
amounts paid by Tenant shall be refunded to Tenant with such statement or, at
Landlord's option, may be applied to any amounts then payable by Tenant to
Landlord or to the next maturing monthly installment of Annual Basic Rent or
Additional Rent. Any deficiency between the estimated and actual Operating Costs
shall be paid by Tenant to Landlord within thirty (30) days of delivery of such
statement. Any amount owing for a fractional calendar year in the first or final
Lease Years of the Lease Term shall be prorated.

     6.3  Operating Costs - Defined.  For the purposes of this Lease, "Operating
          -------------------------                                    ---------
Costs" shall mean all commercially reasonable and actual costs and expenses
-----                                                                      
accrued, paid or incurred by Landlord, or on Landlord's behalf, in respect of
the use, management, repair, service, insurance, condition, operation and
maintenance of the Project including, but not limited to the following:

          (a) Salaries, wages and benefits of all persons who perform duties in
connection with landscaping, parking, janitorial and general cleaning services
for the Project Common Areas and Building Common Areas, security services and
any and all other employees engaged by or on behalf of Landlord, provided to
reflect the actual amount of time spent performing duties in connection with the
Project as opposed to other properties ;

          (b) Prorated payroll taxes, workmen's compensation, uniforms and
related expenses for such employees;

          (c) The cost of all charges for oil, gas, electricity, any alternate
source of energy, heat, ventilation, air-conditioning, refrigeration, water,
sewer service, trash collection, termite and pest control and all other
utilities, together with any taxes on such utilities provided to the Project
Common Areas or the Building Common Areas;

          (d) The cost of painting the Building Common Areas and Project Common
Areas;

          (e) The cost of all charges for rent, casualty, liability, fidelity
and other insurance maintained by Landlord, including any deductible amounts
incurred with respect to an insured loss (subject to Section 6.4 hereof);
                                                     -----------         

          (f) The cost of all supplies (including cleaning supplies), tools,
materials, equipment and personal property, the rental thereof and sales,
transaction privilege, excise and other taxes thereon;

          (g) Depreciation of hand tools and other moveable equipment;

          (h) The cost of all charges for window and other cleaning, janitorial,
security, refuse and lot sweeping;

          (i) The cost of charges for independent contractors;

          (j) The cost of repairs and replacements made by Landlord at its
expense and the fees and other charges for maintenance and service agreements;

          (k) The cost of exterior and interior landscaping;

          (l) Costs relating to the operation and maintenance of all real
property and improvements appurtenant to the Project, including, without
limitation, all parking areas, service areas, walkways and landscaping;

          (m) The cost of alterations and improvements made by reason of the
laws and requirements of any public authorities or the requirements of insurance
bodies not in effect on the Commencement Date;

          (n) All management fees and other charges for management services and
overhead costs (including travel and related expenses), whether provided by an
independent management company, Landlord or an affiliate of Landlord, not to
exceed, however, the then prevailing range of rates charged in comparable office
buildings in the Phoenix, Arizona metropolitan area;

          (o) The cost of any capital improvements or additions which improve
the comfort or amenities available to tenants of the Project, provided, however,
that any such costs shall be amortized with interest over the useful life of the
improvement or addition in accordance with generally accepted accounting
principles, consistently applied ("GAAP");
                                   ----   

                                       5
<PAGE>
 
          (p) The cost of any capital improvements or additions which are
intended to enhance the safety of the Project or reduce (or avoid increases in)
Operating Costs, provided, however, that any such costs shall be amortized in
accordance with GAAP with interest over the useful life of the improvement or
addition;

          (q) The cost of licenses and permits, inspection fees and reasonable
legal, accounting and other professional fees and expenses;

          (r) Taxes (as hereinafter defined);

          (s) Costs relating to the use, management, repair, service, insurance,
condition, operation and maintenance of the Project Common Areas;

          (t) Costs of monitoring and maintaining good internal air quality in
the Building and regularly inspecting, monitoring, maintaining and repairing the
Building's air quality systems, hiring outside consultants to investigate and
identify the sources of any suspected internal air quality problems that may be
identified, remedying any such problems, modifying, renovating or encapsulating
any portion of the Building, or systems or components thereof reasonably
required in order to continuously and efficiently maintain reasonably acceptable
internal air quality in the Building and comply with any and all local, state
and federal regulations, or real estate industry standards relating to internal
air quality; and

          (u) All other charges properly allocable to the use, management,
repair, service, insurance, condition, operation and maintenance of the Project
in accordance with GAAP.

     6.4  Operating Costs - Exclusions.  Excluded from Operating Costs shall be
          ----------------------------                                         
the following:  (a) depreciation, except to the extent expressly included
pursuant to Article 6.3(g) above; (b) principal, fees and interest on and
            --------------                                               
amortization of debts, except to the extent expressly included pursuant to
Article 6.3(o) and (p) above; (c) leasehold improvements, including redecorating
----------------------                                                          
made for tenants of the Building; (d) brokerage commissions and advertising
expenses for procuring tenants for the Building; (e) refinancing costs; (f) the
cost of any repair, replacement or addition which would be required to be
capitalized under GAAP, except to the extent expressly included pursuant to
Articles 6.3(o) and 6.3(p) above; (g) the cost of any item included in Operating
--------------------------                                                      
Costs under Article 6.3 above to the extent that such cost is reimbursable or
            -----------                                                      
payable directly by an insurance company, condemnor, a tenant of the Project or
any other party; (h) the cost of any item included in Operating Costs under
Article 6.3 above to the extent that such cost is attributable to the use,
-----------                                                               
management, repair, service, insurance, condition, operation or maintenance of
other office buildings in the Project; (i) the cost of any item included in
Operating Costs under Article 6.3 above to the extent that such cost is
                      -----------                                      
attributable to the use, management, repair, service, insurance, condition,
operation or maintenance of the Project Common Areas, to the extent such cost is
payable by tenants of other office buildings in the Project, (j) costs
occasioned by the act, omission or violation of any law by Landlord, or its
agents, employees or contractors; (k) other than the deductible, costs
occasioned by fire or other casualties or by the exercise of the power of
eminent domain; (l) costs to correct any patent construction defect or deferred
maintenance in the project or to comply with any covenant, condition,
restriction, underwriter's requirement or law applicable to the project on the
Commencement Date; (m) costs of any renovation, improvement or redecorating of
any portion of the Project not made available for Tenant's use; (n) fees,
commissions, attorneys' fees, and other costs incurred in connection with
negotiations or disputes with any other occupant (or potential occupant) of the
Project and costs arising from the violation by Landlord or any other occupant
of the Project of the terms and conditions of any lease or other agreement; (o)
costs incurred in connection with the remediation of any Hazardous Material,
except to the extent caused by the release or emission of the Hazardous Material
in question by Tenant; (p) rent under ground leases; (q) expense reserves; (r)
any fee, profit or compensation retained by Landlord or its affiliates for
management and administration of the project in excess of the management fee
described in Article 6.3(n) above; and (s) insurance deductibles in excess of
             --------------                                                  
$20,000.00.

     6.5  Taxes - Defined.  For the purposes of this Lease, "Taxes" shall mean
          ---------------                                    -----            
and include all real property taxes and personal property taxes, general and
special assessments (of which there are none presently), foreseen as well as
unforeseen, which are levied or assessed upon or with respect to the Project,
any improvements, fixtures, equipment and other property of Landlord, real or
personal, located on the Project and used in connection with the operation of
all or any portion of the Project, as well as any tax, surcharge or assessment
which shall be levied or assessed in addition to or in lieu of such real or
personal property taxes and assessments.  Taxes shall also include any expenses
incurred by Landlord in contesting the amount or validity of any real or
personal property taxes and assessments.  Taxes shall not, however, include any
franchise, gift, estate, inheritance, conveyance, transfer or income tax
assessed against Land-

                                       6
<PAGE>
 
lord.  "Taxes" shall not include and Tenant shall not be required to pay any
portion of any tax or assessment expense or any increase therein or imposed on
land and improvements other than the Project.

     6.6  No Waiver.  The failure by Landlord to furnish Tenant with a statement
          ---------                                                             
of Operating Costs shall not constitute a waiver by Landlord of its right to
require Tenant to pay excess Operating Costs per rentable square foot.
Notwithstanding anything to the contrary in this Lease, Tenant or its authorized
representative shall have the right to inspect the books of Landlord for the
purpose of verifying the information contained in Landlord's statement of
Operating Costs.  If Landlord's statement of Operating Costs exceeds the actual
Operating Costs by more than five percent (5%), the cost of the audit shall be
paid by Landlord.  In order to exercise such audit right, Tenant must notify
Landlord within six (6) months after Tenant's receipt of Landlord's statement of
Operating Costs and must furnish to Landlord the audit results not later than
ninety (90) days thereafter.

                     7.  CONDITION, REPAIRS AND ALTERATIONS
                         ----------------------------------

     7.1  Condition.  The respective obligations of Landlord and Tenant with
          ---------                                                         
respect to the condition of the Leased Premises are set forth on Exhibit G to
                                                                 ---------   
this Lease.

     7.2  Alterations and Improvements.  Tenant may place partitions and
          ----------------------------                                  
fixtures and may make improvements and other alterations to the interior of the
Leased Premises at Tenant's expense, provided, however, that prior to commencing
any such work, Tenant shall first obtain the written consent of Landlord to the
proposed work, which shall not be unreasonably withheld, including the plans,
specifications, the proposed architect and/or contractor(s) for such alterations
and/or improvements and the materials used in connection with such alterations,
including, without limitation, paint, carpeting, wall or window coverings and
the use of carpet glues and other chemicals for installation of such materials.
At least ten (10) days prior to the commencement of any construction in the
Leased Premises, Tenant shall deliver to Landlord copies of the plans and
specifications for the contemplated work and shall identify the contractor(s)
selected by Tenant to perform such work.  Landlord may, as a condition to
consenting to such work, require that Tenant provide security adequate in
Landlord's judgment so that the improvements or other alterations to the Leased
Premises will be completed in a good, workmanlike and lien free manner.
Landlord may also require that any work done to the interior of the Leased
Premises be subject to the supervision of Landlord or its designee.  All such
improvements or alterations must conform to and be in substantial accordance in
quality and appearance with the quality and appearance of the improvements in
the remainder of the Leased Premises.  All such improvements shall be the
property of Landlord.  In the event Landlord consents to the use by Tenant of
its own architect and/or contractor for the installation of any such alterations
or improvements, prior to the commencement of such work, Tenant shall provide
Landlord with evidence that Tenant's contractor has procured worker's
compensation, liability and property damage insurance (naming Landlord as an
additional insured) in a form and in an amount reasonably approved by Landlord,
and evidence that Tenant's architect and/or contractor has procured the
necessary permits, certificates and approvals from the appropriate governmental
authorities.  Tenant acknowledges and agrees that any review by Landlord of
Tenant's plans and specifications and/or right of approval exercised by Landlord
with respect to Tenant's architect and/or contractor is for Landlord's benefit
only and Landlord shall not, by virtue of such review or right of approval, be
deemed to make any representation, warranty or acknowledgment to Tenant or to
any other person or entity as to the adequacy of Tenant's plans and
specifications or as to the ability, capability or reputation of Tenant's
architect and/or contractor.  Notwithstanding anything to the contrary herein,
Tenant may construct interior nonstructural alterations, additions and
improvements in the Leased Premises without Landlord's prior approval, if the
cost of such work does not exceed in the aggregate Fifty Thousand Dollars
($50,000.00) in any calendar year.  All trade fixtures and personal property
installed in the Leased Premises at Tenant's expense ("Tenant's Property") shall
                                                       -----------------        
at all times remain Tenant's property and Tenant shall be entitled to all
depreciation, amortization and other tax benefits with respect thereto.  Except
for alterations and improvements which cannot be removed without structural
injury to the Leased Premises, at any time Tenant may remove Tenant's Property
from the Leased Premises, provided Tenant repairs all damage caused by such
removal.

     7.3  Tenant's Obligations.  Tenant shall, at Tenant's sole cost and
          --------------------                                          
expense, repair, replace and maintain the Leased Premises in a clean, neat and
sanitary condition and shall keep the Leased Premises and every part thereof in
good condition and repair (except where the same is required to be done by
Landlord or is due to ordinary wear and tear, casualties and condemnation)
including, without limitation, the utility meters, pipes and conduits, all
fixtures, air conditioning and heating equipment serving the Leased Premises and
other equipment therein, all of Tenant's signs, locks and closing devices, all
window sachets, casements or frames, doors and door frames, floor coverings,
including carpeting, terrazzo or other special floor covering, and all such
items of repair, maintenance, alteration and improvement or reconstruction as
may at any time or from time to time be required by a governmental authority
having jurisdiction whether or not

                                       7
<PAGE>
 
presently in effect or anticipated, including, but not limited to, enforcement
of the Americans With Disabilities Act. Notwithstanding anything to the contrary
herein, Landlord shall be solely responsible for, and Tenant shall not have any
responsibility to cause or pay the cost of causing the Leased Premises or the
Project to comply with, any laws, rules or regulations requiring capital
expenditures unless the compliance with any of the foregoing is necessitated
solely due to Tenant's particular use of the Leased Premises. Tenant hereby
waives all rights to make repairs at the expense of Landlord as provided by any
law, statute or ordinance now or hereafter in effect. All of Tenant's
alterations and/or improvements are the property of the Landlord, and Tenant
shall, upon the expiration or earlier termination of the Lease Term, surrender
the Leased Premises, including Tenant's alterations and/or improvements, to
Landlord, janitorial clean and in the same condition as when received, ordinary
wear and tear excepted. Except as set forth in Article 7.4 below, Landlord has
                                               ----------- 
no obligation to construct, remodel, improve, repair, decorate or paint the
Leased Premises or any improvement thereon or part thereof. Tenant shall pay for
the cost of all repairs to the Leased Premises not required to be made by
Landlord and shall be responsible for any redecorating, remodeling, alteration
and painting during the Lease Term as Tenant deems necessary. Tenant shall pay
for any repairs to the Leased Premises, the Building and/or the Project made
necessary by any negligence or carelessness of Tenant, its employees or
invitees.

     7.4  Landlord's Obligations.  Landlord shall (a) maintain and make all
          ----------------------                                           
necessary repairs and replacements to the exterior walls, floors, roof structure
and membrane, structural portions of the Project, including load bearing walls,
at Landlord's sole cost and not as an Operating Cost, (b) maintain and make all
necessary repairs and replacements to the exterior doors, windows and corridors
of the Building, (c) keep the Building, the Building Common Areas and the
Project Common Areas in a clean, neat and attractive condition, (d) maintain as
a component of Operating Expenses the heating, ventilating, air conditioning,
electrical, water, sewer, sprinkler and plumbing systems serving the Leased
Premises, including the pipes and conduits, (e) make repairs necessitated by the
acts or omissions of Landlord or its respective agents, employees or
contractors, (f) make repairs required as a consequence of any construction
defects in the Project, and (g) be responsible for those repairs which would be
treated as a "capital expenditure" under GAAP,

     7.5  Removal of Alterations.  Upon the expiration or earlier termination of
          ----------------------                                                
this Lease, Tenant shall remove from the Leased Premises all movable trade
fixtures and other movable personal property, and shall promptly repair any
damage to the Leased Premises, the Building and/or the Project caused by such
removal.  All such removal and repair shall be entirely at Tenant's sole cost
and expense.  Immediately upon any termination of this Lease, Landlord may
require that Tenant remove from the Leased Premises any alterations, additions,
improvements (other than the Tenant Improvements), trade fixtures, equipment,
shelving, cabinet units or movable furniture (and other personal property)
designated by Landlord to be removed.  In such event, Tenant shall, in
accordance with the provisions of Article 7.2 above, complete such removal
                                  -----------                             
(including the repair of any damage caused thereby) entirely at its own expense
and within fifteen (15) days after notice from Landlord.  All repairs required
of tenant pursuant to the provisions of this Article 7.5 shall be performed in a
                                             -----------                        
manner reasonably satisfactory to Landlord, and shall include, but not be
limited to, repairing plumbing, electrical wiring and holes in walls, restoring
damaged floor and/or ceiling tiles, repairing any other cosmetic damage, and
cleaning the Leased Premises.

     7.6  No Abatement.  Except as provided herein, Landlord shall have no
          ------------                                                    
liability to Tenant, nor shall Tenant's covenants and obligations under this
Lease, including without limitation, Tenant's obligation to pay Annual Basic
Rent and Additional Rent, be reduced or abated in any manner whatsoever by
reason of any inconvenience, annoyance, interruption or injury to business
arising from Landlord's making any repairs or changes which Landlord is required
or permitted to make pursuant to the terms of this Lease or by any other
tenant's Lease or are required by law to be made in and to any portion of the
Leased Premises, the Building or the Project.  Landlord shall, nevertheless, use
reasonable efforts to minimize any interference with Tenant's business in and
access to the Leased Premises and/or Building Common Areas.

                                 8.  SERVICES
                                     --------

     8.1  Climate Control.  Landlord shall provide reasonable climate control to
          ---------------                                                       
the Building Common Areas during the Building Hours as is suitable, in
Landlord's judgment, for the comfortable use and occupation of the Building
Common Areas.

     8.2  Janitorial Services.  Landlord shall make janitorial and cleaning
          -------------------                                              
services available to the Building Common Areas and the Project Common Areas.
Tenant shall be responsible and shall procure janitorial and cleaning services
for the interior of the Leased Premises.


     8.3  Electricity.  Electricity shall be separately metered and Tenant shall
          -----------                                                           
be solely responsible 

                                       8
<PAGE>
 
for the cost of all electric current furnished to the Leased Premises. Tenant's
use of electric energy in the Leased Premises shall not at any time exceed the
capacity of any of the risers, piping, electrical conductors and other equipment
in or serving the Leased Premises. In order to insure that such capacity is not
exceeded and to avert any possible adverse effect on the Building's electric
system, Tenant shall not, without Landlord's prior written consent in each
instance, connect appliances, machines using current in excess of 120 volts or
heavy-duty equipment other than equipment normally used in accordance with the
Permitted Use to the Building's electric system or make any alterations or
additions to the Building's electric system. Should Landlord grant such consent,
all additional risers, piping and electrical conductors and other equipment
therefor shall be provided by Landlord and the cost thereof shall be paid by
Tenant within thirty (30) days after receipt of Landlord's bill.

     8.4  Water.  Landlord shall furnish cold and heated water for drinking and
          -----                                                                
lavatory purposes to the Building Common Areas.

     8.5  Interruptions in Service.  Landlord does not warrant  that any of the
          ------------------------                                             
foregoing services or any other services which Landlord may supply will be free
from interruption.  Tenant acknowledges that any one or more of such services
may be suspended by reason of accident, repairs, inspections, alterations or
improvements necessary to be made, or by strikes or lockouts, or by reason of
operation of law, or by causes beyond the reasonable control of Landlord.
Landlord shall not be liable for and Tenant shall not be entitled to any
abatement or reduction of Annual Basic Rent or Additional Rent by reason of any
disruption of the services to be provided by Landlord pursuant to this Lease.
Notwithstanding anything to the contrary herein, if the Leased Premises should
become not reasonably suitable for Tenant's use such that Tenant cannot occupy
the Leased Premises as a consequence of a cessation of utilities or other
services which (a) is caused by Landlord or Landlord's agents, contractors or
employees or (b) covered by Landlord's insurance, for a period of seven (7)
consecutive calendar days, then Tenant shall be entitled to an equitable
abatement of Rent to the extent of the interference with Tenant's use of the
Leased Premises occasioned thereby.  If the interference persists for more than
one hundred twenty (120) consecutive calendar days, Tenant shall have the right
to terminate this Lease.

                      9.  LIABILITY AND PROPERTY INSURANCE
                          --------------------------------

     9.1  Liability Insurance.  Tenant shall, during the Lease Term, keep in
          -------------------                                               
full force and effect, a policy or policies of commercial general liability
insurance for personal injury (including wrongful death) and damage to property
covering (a) any occurrence in the Leased Premises, (b) any act or omission by
Tenant, by any subtenant of Tenant, or by any of their respective invitees,
agents, servants or employees anywhere in the Leased Premises or the Project,
(c) the business operated by Tenant and by any subtenant of Tenant in the Leased
Premises, and (d) the contractual liability of Tenant to Landlord pursuant to
the indemnification provisions of Article 1.61 below, which coverage shall not
                                  ------------
be less than One Million and No/100 Dollars ($1,000,000.00) per occurrence and
Two Million and No/100 Dollars ($2,000,000.00) combined single limit. The
liability policy or policies shall contain an endorsement naming Landlord, its
partners and any persons, firms or corporations designated by Landlord as
additional insureds, and shall provide that the insurance carrier shall have the
duty to defend and/or settle any legal proceeding filed against Landlord seeking
damages based upon bodily injury or property damage liability even if any of the
allegations of such legal proceedings are groundless, false or fraudulent.

     9.2  Property Insurance.  Tenant shall, during the Lease Term, keep in full
          ------------------                                                    
force and effect, a policy or policies of insurance with "Special Form
Coverage," including coverage for vandalism or malicious mischief, insuring the
Tenant's alterations and/or improvements made pursuant to Article 7.2 above
                                                          -----------      
(which is not covered by Landlord's insurance) and Tenant's stock in trade,
furniture, personal property, fixtures, equipment and other items in the Leased
Premises, with coverage in an amount equal to the full replacement cost thereof.

     9.3  Worker's Compensation Insurance.  Tenant shall, during the Lease Term,
          -------------------------------                                       
keep in full force and effect, a policy or policies of worker's compensation
insurance with an insurance carrier and in amounts approved by the Industrial
Commission of the State of Arizona.

     9.4  Business Interruption Insurance.  Tenant shall, during the Lease Term,
          -------------------------------                                       
keep in full force and effect, a policy or policies of business interruption
insurance in an amount equal to twelve (12) monthly installments of Annual Basic
Rent and Additional Rent payable to Landlord, together with the taxes thereon,
insuring Tenant against losses sustained by Tenant as a result of any cessation
or interruption of Tenant's business in the Leased Premises for any reason.

     9.5  Insurance Requirements.  Each insurance policy and certificate thereof
          ----------------------                                                
obtained by Tenant 

                                       9
<PAGE>
 
pursuant to this Lease shall contain a clause that the insurer will provide
Landlord, its partners and any persons, firms or corporations designated by
Landlord with at least thirty (30) days prior written notice of any material
reduction, non-renewal or cancellation of the policy. Each such insurance policy
shall be with an insurance company authorized to do business in the State of
Arizona and reasonably acceptable to Landlord. Certified copies of all insurance
policies evidencing the coverage under each such policy, as well as a certified
copy of the required additional insured endorsement(s) shall be delivered to
Landlord prior to commencement of the Lease Term. Each such policy shall provide
that any loss payable thereunder shall be payable notwithstanding (a) any act,
omission or neglect by Tenant or by any subtenant of Tenant, or (b) any
occupation or use of the Leased Premises or any portion thereof by Tenant or by
any subtenant of Tenant for purposes more hazardous than permitted by the terms
of such policy or policies, or (c) any foreclosure or other action or proceeding
taken by any mortgagee or trustee pursuant to any provision of any mortgage or
deed of trust covering the Leased Premises, the Building or the Project, or (d)
any change in title or ownership of the Project. All insurance policies required
pursuant to this Article 9 shall be written as primary policies, not 
                 ---------
contributing with or in excess of any coverage which Landlord may carry. Tenant
shall procure and maintain all policies entirely at its own expense and shall,
at least twenty (20) days prior to the expiration of such policies, furnish
Landlord with certified copies of replacement policies or renewal certificates
for existing policies in conformance with Accord Form No. 27 (March 1993).
Tenant shall not do or permit to be done anything which shall invalidate the
insurance policies maintained by Landlord or the insurance policies required
pursuant to this Article 9 or the coverage thereunder. If Tenant or any
                 ---------       
subtenant of Tenant does or permits to be done anything which shall increase the
cost of any insurance policies maintained by Landlord (other than the Permitted
Use), then Tenant shall reimburse Landlord for any additional premiums
attributable to any act or omission or operation of Tenant or any subtenant of
Tenant causing such increase in the cost of insurance. Any such amount shall be
payable as Additional Rent within thirty (30) days after receipt by Tenant of a
bill from Landlord. All policies of liability insurance shall name both Landlord
and Tenant (and/or such other party or parties as Landlord may require) as
additional insureds and shall be endorsed to indicate that the coverage provided
shall not be invalid due to any act or omission on the part of Landlord.

     9.6  Co-Insurance.  If on account of the failure of Tenant to comply with
          ------------                                                        
the provisions of this Article 9, Landlord is deemed a co-insurer by its
                       ---------                                        
insurance carrier, then any loss or damage which Landlord shall sustain by
reason thereof shall be borne by Tenant, and shall be paid by Tenant within
thirty (30) days after receipt of a bill therefor.

     9.7  Adequacy of Insurance.  Landlord makes no representation or warranty
          ---------------------                                               
to Tenant that the amount of insurance to be carried by Tenant under the terms
of this Lease is adequate to fully protect Tenant's interests.  If Tenant
believes that the amount of any such insurance is insufficient, Tenant is
encouraged to obtain, at its sole cost and expense, such additional insurance as
Tenant may deem desirable or adequate.  Tenant acknowledges that Landlord shall
not, by the fact of approving, disapproving, waiving, accepting, or obtaining
any insurance, incur any liability for or with respect to the amount of
insurance carried, the form or legal sufficiency of such insurance, the solvency
of any insurance companies or the payment or defense of any lawsuit in
connection with such insurance coverage, and Tenant hereby expressly assumes
full responsibility therefor and all liability, if any, with respect thereto.

     9.8  Self-Insurance.  Tenant shall have the right to self-insure for the
          --------------                                                     
liability insurance, the property insurance and the business interruption
insurance required by Articles 9.1, 9.2 and 9.4, respectively, subject to the
                      -------------------------
requirements of this Article 9.8.
                     ----------- 

          (a) For purposes of this Article 98, "self-insurance" shall mean that
                                   ----------                                  
Tenant is itself acting as though it were the insurance company providing the
insurance required under the provisions of this Article 9 and Tenant shall pay
                                                ---------                     
any amounts due in lieu of insurance proceeds as required under the provisions
of this Lease, which amounts shall be treated as insurance proceeds for all
purposes under this Lease.

          (b) All amounts which Tenant pays or is required to pay and all losses
or damages resulting from risks for which Tenant has elected to self-insure
shall be subject to the waiver of subrogation provisions in Article 11 below and
                                                            ----------          
shall not limit Tenant's indemnification obligations set forth in Article 16.1
                                                                  ------------
below.

          (c) Tenant's right to self-insure and to continue to self-insure is
conditioned upon and subject to:

              (i) The Tenant having a net worth, calculated in accordance with
     generally accepted accounting principles, consistently applied, of at least
     One Hundred Million Dollars 

                                       10
<PAGE>
 
     ($100,000,000.00).

              (ii) The Tenant providing an audited financial statement,
     prepared in accordance with generally accepted accounting principles,
     consistently applied, to Landlord on or before the date which is thirty
     (30) days prior to the upcoming annual anniversary of the Commencement Date
     which establishes and confirms that Tenant has the required net worth,
     unless events occur that make it apparent that such net worth has
     diminished below the required level (such as the bankruptcy of Tenant), in
     which event Tenant shall not be permitted to continue to self-insure; and

              (iii)  The Tenant maintaining appropriate loss reserves which are
     actuarially derived in accordance with accepted standards of the insurance
     industry and accrued (i.e., charged against earnings) or otherwise funded.

          (d) In the event that Tenant elects to self-insure and an event or
claim occurs for which a defense and/or coverage would have been available from
the insurance company Tenant shall:

              (i) undertake the defense of any such claim, including a defense
     of Landlord, at Tenant's sole cost and expense, and

              (ii) use its own funds to pay any claim or replace any property
     or otherwise provide the funding which would have been available from
     insurance proceeds but for such election by Tenant to self-insure.

          (e) Tenant shall provide Landlord and Superior Mortgagee (defined
below) or Superior Lessor (defined below) with certificates of self-insurance
specifying the extent of self-insurance coverage hereunder and containing a
waiver of subrogation provision reasonably satisfactory to Landlord.  Any
insurance coverage provided by Tenant shall be for the benefit of Landlord, the
Superior Mortgagee and the Superior Lessor as their respective interests may
appear.

     9.9  Landlord's Insurance.  Landlord shall at all times maintain a "special
          --------------------                                                  
form coverage" policy of property insurance, insuring the Project in the amount
of the full replacement value thereof.

                              10.  RECONSTRUCTION
                                   --------------

     10.1 Insured Damage.  In the event the Leased Premises are damaged during
          --------------                                                      
the Lease Term by fire or other perils covered by insurance required to be
carried by Landlord hereunder, Landlord shall:

          (a) Subject to Force Majeure, within a period of ninety (90) days
after receipt by Landlord of insurance proceeds and the adjustment of the loss
with the Superior Mortgagee and/or the Superior Lessor, as the case may be, and
its insurer, but not less than one hundred twenty (120) days after the date of
damage, and provided there is not then in existence of an Event of Default,
commence repair, reconstruction and restoration of the Leased Premises and
prosecute the same diligently to completion, in which event this Lease shall
continue in full force and effect.

          (b) In the event of a partial or total destruction of the Leased
Premises during the last one (1) year of the Lease Term, Landlord or Tenant
shall have the option to terminate this Lease upon giving written notice within
sixty (60) days after such destruction.  For purposes of this Article 10,
                                                              ---------- 
"partial destruction" shall be deemed destruction to an extent of at least
--------------------                                                      
thirty-three and one-third percent (33.33%) of the then full replacement cost of
the Leased Premises, the Building or the Project as of the date of destruction.

          (c) Unless the subordination, nondisturbance and attornment agreement
between Superior Mortgagee and Tenant provides otherwise, in the event that
Superior Mortgagee shall require that insurance proceeds be applied against the
principal balance due on the Superior Mortgage (defined below), then Landlord
may, at Landlord's option and upon sixty (60) days written notice to Tenant,
elect to terminate this Lease.

     10.2 Uninsured Damage.  In the event the Leased Premises shall be damaged
          ----------------                                                    
as a result of any casualty not normally covered by insurance required to be
carried by Landlord hereunder, to any extent whatsoever, Landlord may, subject
to Force Majeure, within one hundred eighty (180) days following the date of the
casualty, commence repair, reconstruction or restoration of the Leased Premises,
in which event this Lease shall continue in full force and effect, or within
such one hundred eighty (180) day period elect

                                       11
<PAGE>
 
not to so repair, reconstruct or restore the Leased Premises, in which event
this Lease shall cease and terminate. In either event, Landlord shall give
Tenant written notice of Landlord's intention within such one hundred eighty
(180) day period. Notwithstanding anything to the contrary herein, Landlord
shall not have the right to terminate this Lease if the damage is relatively
minor (e.g., repair or restoration would cost less than five percent (5%) of the
replacement cost of the Leased Premises), and Tenant agrees to pay the cost of
repair in excess of five percent (5%) of the replacement cost of the Leased
Premises.

     10.3 Reconstruction.  In the event of any reconstruction of the Leased
          --------------                                                   
Premises, the Building or the Project pursuant to this Article 10, such
                                                       ----------      
reconstruction shall be in conformity with all city, county, state and federal
ordinances, rules and regulations then in existence, as the same may be
interpreted and enforced. Notwithstanding that all reconstruction work shall be
performed by Landlord's contractor unless Landlord shall otherwise agree in
writing, Landlord's obligation to reconstruct the Leased Premises shall be only
to the comparable condition of the Leased Premises as of the Commencement Date.
Tenant, at Tenant's sole cost and expense, shall be responsible for the repair
and restoration of all items of the Tenant's improvements and/or alterations
installed pursuant to Article 72.  Tenant shall commence the installation of
                      ----------                                            
fixtures promptly upon delivery to Tenant of possession of the Leased Premises
and shall diligently prosecute such installation to completion.

     10.4 Termination.  Upon any termination of this Lease under any of the
          -----------                                                      
provisions of this Article 10, Landlord and Tenant each shall be released
                   ----------                                            
without further obligations to the other coincident with the surrender of
possession of the Leased Premises to Landlord, except for items which have
previously accrued and remain unpaid.  Notwithstanding anything to the contrary
herein, if the Leased Premises are damaged by any peril and Landlord does not
elect to terminate this Lease or is not entitled to terminate this Lease
pursuant to its terms, then Tenant shall have the option to terminate this Lease
if the Leased Premises cannot be (as determined by Landlord in its commercially
reasonable judgment), or are not in fact, fully restored by Landlord to their
prior condition within one hundred eighty (180) days after the damage.
Notwithstanding anything to the contrary herein, Landlord will not terminate
this Lease if Landlord commences to rebuild the Leased Premises within one
hundred eighty (180) days of the date of casualty.

     10.5 Abatement.  In the event of repair, reconstruction and restoration of
          ---------                                                            
the Leased Premises, the Minimum Annual Rental and Additional Rent shall be
abated proportionately with the degree to which Tenant's use of the Leased
Premises is impaired commencing from the date of destruction and continuing
during the period of such repair, reconstruction or restoration.  Tenant shall
not be entitled to any compensation or damages from Landlord for loss of the use
of the whole or any part of the Leased Premises, or the building of which the
Leased Premises are a part, Tenant's personal property or for any inconvenience
or annoyance occasioned by such damage, repair, reconstruction or restoration.

     10.6 Waiver.  Tenant hereby waives any statutory and common law rights of
          ------                                                              
termination which may arise by reason of any partial or total destruction of the
Leased Premises which Landlord is obligated to restore or may restore under any
of the provisions of this Lease, including the provisions of A.R.S. (S) 33-343.

                          11.  WAIVER OF SUBROGATION
                               ---------------------

     Notwithstanding anything to the contrary herein, Landlord and Tenant each
hereby waive any rights one may have against the other on account of any loss or
damage occasioned to Landlord or Tenant, as the case may be, or their respective
property, the Leased Premises, its contents or to other portions of the Building
and the Project arising from any risk generally covered by fire and extended
insurance and from any risk covered by property insurance then in effect.  In
addition, Landlord and Tenant, for themselves and on behalf of their respective
insurance companies, waive any right of subrogation that any such insurance
company may have against Landlord, Landlord's lender, any other tenant of the
Project, or Tenant, as the case may be.  The foregoing waivers of subrogation
shall be operative only so long as available in the State where the Project is
situated and provided further that no policy of insurance is invalidated
thereby.  Each party shall use its best efforts to cause each property insurance
policy it obtains to provide that the insurer thereunder waives all right of
recovery by way of subrogation as required herein in connection with any injury
or damage covered by the policy.  If the insurance policy cannot be obtained
with the waiver of subrogation, or if the waiver of subrogation is available
only at additional cost and the party for whose benefit the waiver is not
obtained does not pay the additional cost, then the party obtaining the
insurance immediately shall notify the other party.

                                       12
<PAGE>
 
              12.  LANDLORD'S RIGHT TO PERFORM TENANT OBLIGATIONS
                   ----------------------------------------------

     All covenants and agreements to be performed by Tenant under any of the
terms of this Lease shall be performed by Tenant at Tenant's sole cost and
expense and without any abatement of Annual Basic Rent or Additional Rent.  If
Tenant shall fail to pay any sum of money, other than Annual Basic Rent,
required to be paid by it hereunder, or shall fail to perform any other act on
its part to be performed hereunder, and such failure shall continue for the
period set forth in section 13 hereof after notice thereof by Landlord (or such
                    ----------                                                 
shorter period of time as may be reasonable following oral notice to Tenant's
personnel in the Leased Premises in the case of emergency), Landlord may (but
shall not be obligated to do so)  without waiving or releasing Tenant from any
of Tenant's obligations, make any such payment or perform any such other act on
behalf of Tenant.  All sums so paid by Landlord and all necessary incidental
costs, together with interest thereon at the greater of (a) fifteen percent
(15%) per annum or (b) the rate of interest per annum publicly announced, quoted
or published, from time to time, by Bank of America, at its Phoenix, Arizona
office as its "reference rate" plus four (4) percentage points, from the date of
such payment by Landlord until reimbursement in full by Tenant (the "Default
                                                                     -------
Rate"), shall be payable to Landlord as Additional Rent with the next monthly
----                                                                         
installment of Annual Basic Rent; provided, however, in no event shall the
Default Rate exceed the maximum rate (if any) permitted by applicable law.

                           13.  DEFAULT AND REMEDIES
                                --------------------

     13.1 Event of Default.  The occurrence of any one or more of the following
          ----------------                                                     
events will constitute an "Event of Default" on the part of Tenant:
                           ----------------                        

          (a) Failure to pay any installment of Annual Basic Rent, any
Additional Rent or any other sum required to be paid by Tenant under this Lease,
and such failure shall continue for five (5) business days after written notice
thereof by Landlord to Tenant;

          (b) Failure to perform any of the other covenants or conditions which
Tenant is required to observe and perform (except failure in the payment of
Annual Basic Rent, Additional Rent or any other monetary obligation contained in
this Lease) and such failure shall continue for thirty (30) days after written
notice thereof by Landlord to Tenant, provided that if such default is other
than the payment of money and cannot be cured within such thirty (30) day
period, then an Event of Default shall not have occurred if Tenant, within such
thirty (30) period, commences curing of such failure and diligently in good
faith prosecutes the same to completion and furnishes evidence thereof to
Landlord as soon as is reasonably practical thereafter.

          (c) If any warranty, representation or statement made by Tenant to
Landlord in connection with this Lease is or was intentionally and materially
false or misleading when made or furnished;

          (d) The levy of a writ of attachment or execution or other judicial
seizure of substantially all of Tenant's assets or its interest in this Lease,
such attachment, execution or other seizure remaining undismissed or discharged
for a period of sixty (60) days after the levy thereof;

          (e) The filing of any petition by or against Tenant or any Guarantor
to declare Tenant or any Guarantor a bankrupt or to delay, reduce or modify
Tenant's or any Guarantor's debts or obligations, which petition is not
discharged within sixty (60) days after the date of filing;

          (f) The filing of any petition or other action taken to reorganize or
modify Tenant's or any Guarantor's capital structure, which petition is not
discharged within sixty (60) days after the date of filing;

          (g) If Tenant or any Guarantor shall be declared insolvent according
to law;

          (h) A general assignment by Tenant or any Guarantor for the benefit of
creditors;

          (i) The appointment of a receiver or trustee for Tenant or any
Guarantor or all or any of their respective property, which appointment is not
discharged within sixty (60) days after the date of filing; or

          (j) The filing by Tenant or any Guarantor of a voluntary petition
pursuant to the Bankruptcy Code or any successor thereto or the filing of an
involuntary petition against Tenant or any Guarantor pursuant to the Bankruptcy
Code or any successor legislation, which petition is not discharged 

                                       13
<PAGE>
 
within sixty (60) days after the date of filing.

     13.2  Remedies.  Upon the occurrence of an Event of Default under this
           --------                                                        
Lease by Tenant, Landlord may, without prejudice to any other rights and
remedies available to a landlord at law, in equity or by statute, Landlord may
exercise one or more of the following remedies, all of which shall be construed
and held to be cumulative and non-exclusive:  (a) Terminate this Lease and re-
enter and take possession of the Leased Premises, in which event, Landlord is
authorized to make such repairs, redecorating, refurbishments or improvements to
the Leased Premises as may be necessary in the reasonable opinion of Landlord
acting in good faith for the purposes of reletting the Leased Premises and the
costs and expenses incurred in respect of such repairs, redecorating and
refurbishments and the expenses of such reletting (including brokerage
commissions attributable to the remainder of the term hereof) shall be paid by
Tenant to Landlord within five (5) days after receipt of Landlord's statement;
or (b) Without terminating this Lease, re-enter and take possession of the
Leased Premises; or (c) Without such re-entry, recover possession of the Leased
Premises in the manner prescribed by any statute relating to summary process,
and any demand for Annual Basic Rent, re-entry  for condition broken, and any
and all notices to quit, or other formalities of any nature to which Tenant may
be entitled, are hereby specifically waived to the extent permitted by law; or
(d) Without terminating this Lease, Landlord may relet the Leased Premises as
Landlord may see fit without thereby avoiding or terminating this Lease, and for
the purposes of such reletting, Landlord is authorized to make such repairs,
redecorating, refurbishments or improvements to the Leased Premises as may be
necessary in the reasonable opinion of Landlord acting in good faith for the
purpose of such reletting, and if a sufficient sum is not realized from such
reletting (after payment of all costs and expenses of such repairs, redecorating
and refurbishments and expenses of such reletting (including brokerage
commissions) and the collection of rent accruing therefrom) each month to equal
the Annual Basic Rent and Additional Rent payable hereunder, then Tenant shall
pay such deficiency each month within five (5) days after receipt of Landlord's
statement; or (e) Landlord may declare immediately due and payable all the
remaining installments of Annual Basic Rent and Additional Rent, and the present
value of such amount, less the present fair rental value of the Leased Premises
for the remainder of the Lease Term shall be paid by Tenant within five (5) days
after receipt of Landlord's statement.  Landlord shall not by re-entry or any
other act, be deemed to have terminated this Lease, or the liability of Tenant
for the total Annual Basic Rent and Additional Rent reserved hereunder or for
any installment thereof then due or thereafter accruing, or for damages, unless
Landlord notifies Tenant in writing that Landlord has so elected to terminate
this Lease.  After the occurrence of an Event of Default, the acceptance of
Annual Basic Rent or Additional Rent, or the failure to re-enter by Landlord
shall not be deemed to be a waiver of Landlord's right to thereafter terminate
this Lease and exercise any other rights and remedies available to it, and
Landlord may re-enter and take possession of the Leased Premises as if no Annual
Basic Rent or Additional Rent had been accepted after the occurrence of an Event
of Default.  Upon an Event of Default, Tenant shall also pay to Landlord all
costs and expenses incurred by Landlord, including court costs and attorneys'
fees, in retaking or otherwise obtaining possession of the Leased Premises,
removing and storing all equipment, fixtures and personal property on the Leased
Premises and otherwise enforcing any of Landlord's rights, remedies or recourses
arising as a result of an Event of Default.

     13.3 Additional Remedies.  All of the remedies given to Landlord in this
          -------------------                                                
Lease in the event Tenant commits an Event of Default are in addition to all
other rights or remedies available to a landlord at law, in equity or by
statute, excluding the right to seize and sell all goods, equipment and personal
property of Tenant located in the Leased Premises and apply the proceeds thereof
to all due and unpaid Annual Basic Rent, Additional Rent and other amounts owing
under the Lease.  All rights, options and remedies available to Landlord shall
be construed and held to be cumulative, and no one of them shall be exclusive of
the other.  During the continuance of an Event of Default which remains uncured,
Tenant shall not be entitled to exercise its options to renew, extend or expand,
contraction rights and any other rights which may be exercised by Tenant.  In
the event that Landlord elects to relet the Leased premises without termination
of the Lease, Tenant shall thereafter be released from all obligations arising
under the Lease accruing after the date of such reletting by Landlord.  Landlord
waives any right to exercise Landlord's lien that may arise at law.

     13.4 Interest on Past Due Amounts.  In addition to the late charge
          ----------------------------                                 
described in Article 14 below, if any installment of Annual Basic Rent or
             ----------                                                  
Additional Rent is not paid within five (5) business days following notice from
Landlord of a delinquency, it shall bear interest at the Default Rate; provided,
however, this provision shall not relieve Tenant from any default in the making
of any payment at the time and in the manner required by this Lease; and
provided, further, in no event shall the Default Rate exceed the maximum rate
(if any) permitted by applicable law.

     13.5 Landlord Default.  In the event Landlord should neglect or fail to
          ----------------                                                  
perform or observe any of the covenants, provisions or conditions contained in
this Lease on its part to be performed or observed, and, 

                                       14
<PAGE>
 
except in the case of an emergency, such failure continues for thirty (30) days
after written notice of default (or if more than thirty (30) days shall be
required because of the nature of the default, if Landlord shall fail to
commence the curing of such default within such thirty (30) day period and
proceed diligently thereafter), then Landlord shall be responsible to Tenant for
any actual damages sustained by Tenant as a result of Landlord's breach, but not
special or consequential damages. Should Tenant give written notice to Landlord
to correct any default, Tenant shall give similar notice to the holder of any
mortgages or deeds of trust against the Building or the lessor of any ground
lease (provided Tenant has been provided the appropriate addresses), and prior
to any cancellation of this Lease, the holder of such mortgage or deed of trust
and/or the lessor under such ground lease shall be given a reasonable period of
time to correct or remedy such default. If and when such holder of such mortgage
or deed of trust and/or the lessor under any such ground lease has made
performance on behalf of Landlord, the default of Landlord shall be deemed
cured.

                              14.  LATE PAYMENTS
                                   -------------

     Tenant hereby acknowledges that the late payment by Tenant to Landlord of
any monthly installment of Annual Basic Rent, any Additional Rent or any other
sums due hereunder will cause Landlord to incur costs not contemplated by this
Lease, the exact amount of which will be extremely difficult and impracticable
to ascertain.  Such costs include but are not limited to processing,
administrative and accounting costs.  Accordingly, if any monthly installment of
Annual Basic Rent, any Additional Rent or any other sum due from Tenant shall
not be received by Landlord within five (5) business days after the date when
due, Tenant shall pay to Landlord a late charge equal to five percent (5%) of
such overdue amount or Two Hundred and No/100 Dollars ($200.00), whichever is
greater. Tenant acknowledges that such late charge represents a fair and
reasonable estimate of the costs Landlord will incur by reason of late payments
by Tenant.  Neither assessment nor acceptance of a late charge by Landlord shall
constitute a waiver of Tenant's default with respect to such overdue amount, nor
prevent Landlord from exercising any of the other rights and remedies available
to Landlord.  Nothing contained in this Article 14 shall be deemed to condone,
                                        ----------                            
authorize, sanction or grant to Tenant an option for the late payment of Annual
Basic Rent, Additional Rent or any other sum due hereunder.  Notwithstanding the
foregoing, prior to assessing a late charge, Landlord shall provide Tenant with
written notice the first time a rental payment is delinquent in a twelve (12)
month period, and no late charge shall be due if Tenant makes the payment within
five (5) days of delivery of such notice.

                        15.  ABANDONMENT AND SURRENDER
                             -------------------------

     15.1 Intentionally Omitted.
          --------------------- 

     15.2 Surrender.  Tenant shall, upon the expiration or earlier termination
          ---------                                                           
of this Lease, peaceably surrender the Leased Premises, including any Tenant
Improvements or Tenant's improvements and/or alterations installed pursuant to
Article 7.2, in a janitorial clean condition and otherwise in as good condition
-----------                                                                    
as when Tenant took possession, except for (i) reasonable wear and tear
subsequent to the last  required repair, replacement, restoration, alteration or
renewal; (ii) loss by fire or other casualty, (iii) loss by condemnation; (iv)
Landlord's obligations hereunder; and (v) Hazardous Materials not released,
discharged, brought onto or otherwise disposed of by Tenant or its agents,
invitees, employees or contractors.  If Tenant shall surrender the Leased
Premises, or be dispossessed by process of law or otherwise, any personal
property and fixtures belonging to Tenant and left in the Leased Premises shall
be deemed abandoned and, at Landlord's option, title shall pass to Landlord
under this Lease as by a bill of sale.  Landlord may, however, if it so elects,
remove all or any part of such personal property from the Leased Premises and
the costs incurred by Landlord in connection with such removal, including
storage costs and the cost of repairing any damage to the Leased Premises, the
Building and/or the Project caused by such removal shall be paid by Tenant
within five (5) days after receipt of Landlord's statement.  Upon the expiration
or earlier termination of this Lease, Tenant shall surrender to  Landlord all
keys to the Leased Premises and shall inform Landlord of the combination of any
vaults, locks and safes left on the Leased Premises.  The obligations of Tenant
under this Article 15.2 shall survive the expiration or earlier termination of
           ------------                                                       
this Lease.  Tenant shall indemnify Landlord against any loss or liability
resulting from delay by Tenant in so surrendering the Premises, including,
without limitation, any claims made by any succeeding Tenant founded on such
delay.  Landlord and Tenant shall jointly inspect the Leased Premises upon the
termination of this Lease.

                                       15
<PAGE>
 
                      16.  INDEMNIFICATION AND EXCULPATION
                           -------------------------------

     16.1 Indemnification.  Tenant shall indemnify, protect, defend and hold
          ---------------                                                   
Landlord harmless from and against, and shall be responsible for, all claims,
damages, losses, costs, liens, encumbrances, liabilities and expenses, including
reasonable attorneys', accountants' and investigators' fees and court costs (col
lectively, the "Claims"), however caused, arising in whole or in part from
                ------                                                    
Tenant's use of all or any part of the Leased Premises, the Building and/or the
Project or the conduct of Tenant's business or from any activity, work or thing
done by Tenant or by any invitee, servant, agent, employee or subtenant of
Tenant in the Leased Premises, the Building and/or the Project, and shall
further indemnify, protect, defend and hold Landlord harmless from and against,
and shall be responsible for, all Claims to the extent arising from any breach
or default in the performance of any obligation on Tenant's part to be performed
under the terms of this Lease or from any act, neglect, fault or omission by
Tenant or by any invitee, servant, agent, employee or subtenant of Tenant
anywhere in the Leased Premises, the Building and/or the Project. In case any
action or proceeding is brought against Landlord to which this indemnification
shall be applicable, Tenant shall pay all Claims resulting therefrom and shall
defend such action or proceeding, if Landlord shall so request, at Tenant's sole
cost and expense, by counsel reasonably satisfactory to Landlord. The
obligations of Tenant under this Article 16.1 shall survive the expiration or
                                 -----------                  
earlier termination of this Lease. Notwithstanding anything to the contrary in
this Lease, Landlord shall not be released or indemnified from Claims arising
from the negligence or willful misconduct of Landlord or its agents,
contractors, licensees or invitees or a breach of Landlord's obligations or
representations under this Lease.

     16.2 Exculpation.  Tenant, as a material part of the consideration to
          -----------                                                     
Landlord, hereby assumes all risk of damage to property, injury and death to
persons and all claims of any other nature resulting from Tenant's use of all or
any part of the Leased Premises, the Building and/or the Project, and Tenant
hereby waives all claims in respect thereof against Landlord.  Neither Landlord
nor its agents or employees shall be liable for any damaged property of Tenant
entrusted to any employee or agent of Landlord or for loss of or damage to any
property of Tenant by theft or otherwise.  Landlord shall not be liable for any
injury or damage to persons or property resulting from any cause, including, but
not limited to, fire, explosion, falling plaster, steam, gas, electricity,
sewage, odor, noise, water or rain which may leak from any part of the Building
or from the pipes, appliances or plumbing works therein, or from the roof of any
structure on the Project, or from any streets or subsurfaces on or adjacent to
the Building or the Project, or from any other place or resulting from dampness
or any other causes whatsoever, except to the extent caused by the negligence or
wilful misconduct of Landlord or its agents, employees or contractors, or
Landlord's breach of this Lease.  Neither Landlord nor its employees or agents
shall be liable for the criminal acts by maintenance or other personnel or
contractors serving the Leased Premises, the Building and/or the Project, other
tenants or third parties, unless Landlord is negligent or guilty of willful
misconduct.  All property of Tenant kept or stored on the Project shall be so
kept or stored at the risk of Tenant only, and Tenant shall indemnify, defend
and hold Landlord harmless from and against, and shall be responsible for, any
Claims arising out of damage to the same, including subrogation claims by
Tenant's insurance carriers, except to the extent such damage shall be caused by
the willful act or neglect of Landlord and through no fault of Tenant. None of
the events or conditions set forth in this Article 16 shall be deemed a
                                           ----------                  
constructive or actual eviction or result in a termination of this Lease, nor
shall Tenant be entitled to any abatement or reduction of Annual Basic Rent or
Additional Rent by reason thereof.  Tenant shall give prompt notice to Landlord
with respect to any defects, fires or accidents which Tenant observes in the
Leased Premises, the Building and/or the Project.

                                       16
<PAGE>
 
                            17.  ENTRY BY LANDLORD
                                 -----------------

     Landlord reserves and shall at any and all times have the right to enter
the Leased Premises at reasonable times and upon twenty four (24) hours notice
(except in the case of an emergency), to inspect the same, to supply janitorial
service and other services to be provided by Landlord to Tenant hereunder, to
submit the Leased Premises to prospective purchasers or (during the last six (6)
months of the Lease term only) tenants, to post notices of non-responsibility,
and to alter, improve or repair the Leased Premises and any portion of the
Building of which the Leased Premises are a part, without abatement of Annual
Basic Rent or Additional Rent, and may for that purpose erect scaffolding and
other necessary structures where reasonably required by the character of the
work to be performed, always providing that access into the Leased Premises
shall not be blocked thereby, and further providing that the business of Tenant
shall not be interfered with unreasonably.  Tenant hereby waives any claim for
damages for any injury or inconvenience to or interference with Tenant's
business, any loss of occupancy or quiet enjoyment of the Leased Premises or any
loss occasioned thereby.  For each of the aforesaid purposes, Landlord shall at
all times have and retain a key with which to unlock all the doors in, upon or
about the Leased Premises, excluding Tenant's vaults and safes, and Landlord
shall have the right to use any and all means which Landlord may deem proper to
open such doors in an emergency in order to obtain entry to the Leased Premises,
and any entry to the Leased Premises obtained by Landlord by any such means or
otherwise shall not under any circumstances be construed or deemed to be a
forcible or unlawful entry into, or a detainer of, the Leased Premises or an
eviction of Tenant from all or any portion of the Leased Premises.  Nothing in
this Article 17 shall be construed as obligating Landlord to perform any
     ----------                                                         
repairs, alterations or maintenance except as otherwise expressly required
elsewhere in this Lease. Notwithstanding anything to the contrary in this Lease,
any entry by Landlord and Landlord's agents shall not impair Tenant's operations
more than reasonably necessary, and shall comply with Tenant's reasonable
security measures.

                                 18.  RESERVED
                                      --------

                        19.  ASSIGNMENT AND SUBLETTING
                             -------------------------

     19.1 Consent of Landlord Required.  Tenant shall not transfer or assign
          ----------------------------                                      
this Lease or any right or interest hereunder, or sublet the Leased Premises or
any part thereof,  without first obtaining Landlord's prior written consent,
which consent shall not be unreasonably withheld.  No transfer or assignment
(whether voluntary or involuntary, by operation of law or otherwise) or
subletting shall be valid or effective without such prior written consent.
Should Tenant attempt to make or allow to be made any such transfer, assignment
or subletting, except as aforesaid, or should any of Tenant's rights under this
Lease be sold or otherwise transferred by or under court order or legal process
or otherwise, then, and in any of the foregoing events Landlord may, at its
option, treat such act as a default by Tenant.  Should Landlord consent to a
transfer, assignment or subletting, such consent shall not constitute a waiver
of any of the restrictions or prohibitions of this Article 19, and such
                                                   ----------          
restrictions or prohibitions shall apply to each successive transfer, assignment
or subletting hereunder, if any.  Notwithstanding the foregoing, Landlord's
consent shall not be required for any sublet, assignment or transfer of the
Leased Premises or this Lease to (a) a subsidiary, affiliate or corporation
controlling, controlled by or under common control with Tenant, (b) a successor
corporation related to Tenant by merger, consolidation, nonbankruptcy
reorganization, or government action, or (c) a purchaser of substantially all of
Tenant's assets or stock (collectively, "Permitted Transfers").
                                         -------------------   

     19.2 Deemed Transfers.  For the purposes of this Article 19 and other than
          ----------------                            ----------               
Permitted Transfers, an assignment shall be deemed to include the following:
(a) if Tenant is a partnership, a withdrawal or change (voluntary, involuntary,
by operation of law or otherwise) of any of the partners thereof, a purported
assignment, transfer, mortgage or encumbrance (voluntary, involuntary, by
operation of law or otherwise) by any partner thereof of such partner's interest
in Tenant, or the dissolution of the partnership; (b) if Tenant consists of more
than one person, a purported assignment, transfer, mortgage or encumbrance
(voluntary, involuntary, by operation of law or otherwise) from one person unto
the other or others; (c) if Tenant (or a constituent partner of Tenant) is a
corporation, any dissolution, merger, consolidation or reorganization of Tenant
(or such constituent partner), or any change in the ownership (voluntary,
involuntary, by operation of law, creation of new stock or otherwise) of fifty
percent (50%) or more of its capital stock in one or a series of related
transactions; (d) if Tenant is an unincorporated association, a purported
assignment, transfer, mortgage or encumbrance (voluntary, involuntary, by
operation of law or otherwise) of any interest in such unincorporated
association; or (e) if Tenant is a limited liability company, a withdrawal or
change of any of the members thereof, a purported assignment, transfer, mortgage
or encumbrance (voluntary, involuntary, by operation of law or otherwise) by any
member of such member's interest in Tenant, or the dissolution of the limited
liability company.

     19.3 Delivery of Information.  If Tenant wishes at any time to assign this
          -----------------------                                              
Lease or sublet the 

                                       17
<PAGE>
 
Leased Premises or any portion thereof, it shall first notify Landlord of its
desire to do so and shall submit in writing to Landlord: (a) the name of the
proposed subtenant or assignee; (b) the nature of the proposed subtenant's or
assignee's business to be carried on in the Leased Premises; (c) the terms and
the provisions of the proposed sublease or assignment; and (d) such financial
information as Landlord may reasonably request concerning the proposed subtenant
or assignee. Tenant's failure to comply with the provisions of this Article 19.3
                                                                    ------------
shall entitle Landlord to withhold its consent to the proposed assignment or
subletting.

     19.4 Recapture.  If Tenant proposes to assign its interest in this Lease or
          ---------                                                             
sublet (for the remainder of the term) all or any part of the Leased Premises
for which Landlord's consent is required, Landlord may, at its option, upon
written notice to Tenant within thirty (30) days after Landlord's receipt of the
information specified in Article 19.3 above, elect to recapture the portion of
                         ------------                                         
the Leased Premises to be assigned or sublet, and within sixty (60) days after
notice of such election has been given to Tenant, this Lease shall terminate as
to the portion of the Leased Premises recaptured unless Tenant within such sixty
(60) day period delivers notice to Landlord rescinding its proposal to assign or
sublet.  If all or a portion of the Leased Premises is recaptured by Landlord
pursuant to this Article 19.4, Tenant shall promptly execute and deliver to
                 ------------                                              
Landlord a termination agreement setting forth the termination date with respect
to the Leased Premises or the recaptured portion thereof, and prorating the
Annual Basic Rent, Additional Rent and other charges payable hereunder to such
date.  If Landlord does not elect to recapture as set forth above, Tenant may
thereafter enter into a valid assignment or sublease with respect to the Leased
Premises, provided that Landlord consents thereto pursuant to this Article 19,
                                                                   ---------- 
and provided further, that (a) such assignment or sublease is executed within
ninety (90) days after Landlord has given its consent, (b) Tenant pays all
amounts then owed to Landlord under this Lease, (c) there is not in existence
an Event of Default as of the effective date of the assignment or sublease, (d)
there have been no material changes with respect to the financial condition of
the proposed subtenant or assignee or the business such party intends to conduct
in the Leased Premises, and (e) a fully executed original of such assignment or
sublease providing for an express assumption by the assignee or subtenant of all
of the terms, covenants and conditions of this Lease is promptly delivered to
Landlord.

     19.5 Adjustment to Rental.  In the event Tenant assigns its interest in
          --------------------                                              
this Lease or sublets the Leased Premises other than a Permitted Transfer, the
Annual Basic Rent set forth in Article 11.2 above, as adjusted, shall be
                               ------------                             
increased effective as of the date of such assignment or subletting by fifty
percent (50%) of the rent and other consideration actually paid by any such
assignee or sublessee pursuant to such assignment or sublease if such assignee
or sublessee is paying rent in excess of the Annual Basic Rent as adjusted,
after first deducting therefrom Tenant's reasonable costs of such assignment or
subletting, including brokerage fees, the unamortized value of improvements to
the Leased Premises paid by Tenant, remodeling costs and attorneys' fees.

     19.6 No Release from Liability.  During the continuance of an Event of
          -------------------------                                        
Default, Landlord may collect Annual Basic Rent and Additional Rent from the
assignee, subtenant, occupant or other transferee, and apply the amount so
collected, first to the monthly installments of Annual Basic Rent, then to any
Additional Rent and other sums due and payable to Landlord, and the balance, if
any, to Landlord, but no such assignment, subletting, occupancy, transfer or
collection shall be deemed a waiver of Landlord's rights under this Article 19,
                                                                    ---------- 
or the acceptance of the proposed assignee, subtenant, occupant or transferee.
Notwithstanding any assignment, sublease or other transfer (with or without the
consent of Landlord), Tenant  shall remain primarily liable under this Lease and
shall not be released from performance of any of the terms, covenants and
conditions of this Lease.

     19.7 Landlord's Expenses.  If Landlord's consent is required to an
          -------------------                                          
assignment, sublease or other transfer by Tenant of all or any portion of
Tenant's interest under this Lease, Tenant shall pay or cause to be paid to
Landlord, a transfer fee to reimburse Landlord for administrative expenses and
for reasonable legal, accounting and other out of pocket expenses actually
incurred by Landlord.

     19.8 Assumption Agreement.  If Landlord consents to an assignment, sublease
          --------------------                                                  
or other transfer by Tenant of all or any portion of Tenant's interest under
this Lease, Tenant shall execute and deliver to Landlord, and cause the
transferee to execute and deliver to Landlord, an instrument in the form and
substance acceptable to Landlord in which (a) the transferee adopts this Lease
and assumes and agrees to perform, jointly and severally with Tenant, all of the
obligations of Tenant hereunder (as to assignments of this Lease only), (b)
Tenant acknowledges that it remains primarily liable for the payment of Annual
Basic Rent, Additional Rent and other obligations under this Lease, (c) Tenant
subordinates to Landlord's statutory lien, contract lien and security interest,
any liens, security interests or other rights which Tenant may claim with
respect to any property of transferee and (d) the transferee agrees to use and
occupy the Leased Premises solely for the purpose specified in Article 20 and
                                                               ----------    
otherwise in strict accordance with this Lease.

                                       18
<PAGE>
 
     19.9 Withholding Consent.  Without limiting the grounds for withholding
          -------------------                                               
consent which may be reasonable, it shall be reasonable for Landlord to withhold
consent if the proposed assignee or subtenant is a tenant in default of such
tenant's lease (or the termination by such assignee or subtenant of such lease
to sublease from Tenant will be a default under same) in a building in the
Phoenix metropolitan area owned by Landlord or by an affiliate of Landlord or
any of Landlord's constituent partners or principals; or if the proposed
assignee or subtenant is a governmental or quasi-governmental entity, agency,
department or any subdivision thereof not already a tenant of Landlord or its
affiliates; or if the use by the proposed assignee or subtenant would violate
the terms of this Lease, or any restrictive use covenant or exclusive rights
granted by Landlord at the Project; or if the nature of the proposed assignee or
subtenant or its business would not be consistent with the operation of a
comparable, high quality building; or if the proposed assignee or subtenant does
not intend to occupy the Premises for its own use, or if the proposed assignee
or subtenant is an existing or prospective tenant of the Project with whom
Landlord or its broker are then negotiating leasing space.

                20.  USE OF LEASED PREMISES AND RUBBISH REMOVAL
                     ------------------------------------------

     20.1 Use.  The Leased Premises are leased to Tenant solely for the
          ---                                                          
Permitted Use set forth in Article 1.9 above and for no other purpose whatsoever
                           -----------                                          
without Landlord's prior written consent, which may be withheld by Landlord in
its sole and absolute discretion.  Tenant shall not use or occupy or permit the
Leased Premises to be used or occupied, nor shall Tenant do or permit anything
to be done in or about the Leased Premises nor bring or keep anything therein
which will in any way increase the existing rate of or affect any casualty or
other insurance on the Building, the Project or any of their respective contents
other than the Permitted Use (unless Tenant pays such increase), or make void or
voidable or cause a cancellation of any insurance policy covering the Building,
the Project or any part thereof or any of their respective contents.  Tenant
shall not do or permit anything to be done in or about the Leased Premises, the
Building and/or the Project which will in any way obstruct or interfere with the
rights of other tenants or occupants of the Building or the Project or injure or
annoy them.  Tenant shall not use or allow the Leased Premises to be used for
any improper, immoral, unlawful or objectionable purpose, nor shall Tenant
cause, maintain or permit any nuisance in, on or about the Leased Premises, the
Building and/or the Project.  In addition, Tenant shall not commit any waste in
or upon the Leased Premises, the Building and/or the Project.  Tenant shall not
use the Leased Premises, the Building and/or the Project or permit anything to
be done in or about the Leased Premises, the Building and/or the Project which
will in any way conflict with any matters of record, or any law, statute,
ordinance or governmental rule or regulation now in force or which may hereafter
be enacted or promulgated, and shall, at its sole cost and expense, promptly
comply with all matters of record and all laws, statutes, ordinances and
governmental rules, regulations and requirements now in force or which may
hereafter be in force and with the requirements of any Board of Fire
Underwriters or other similar body now or hereafter constituted, foreseen or
unforeseen, ordinary as well as extraordinary, relating to or affecting the
condition, use or occupancy of the Project, excluding capital changes not
relating to or affected by Tenant's improvements or acts.  The judgment of any
court of competent jurisdiction or the admission by Tenant in any action against
Tenant, whether Landlord be a party thereto or not, that Tenant has violated any
matters of record, or any law, statute, ordinance or governmental rule,
regulation or requirement, shall be conclusive of that fact between Landlord and
Tenant.  In addition, Tenant shall not place a load upon any floor of the Leased
Premises which exceeds the load per square foot which the floor was designed to
carry, nor shall Tenant install business machines or other mechanical equipment
in the Leased Premises which cause noise or vibration that may be transmitted to
the structure of the Building.

     20.2 Rubbish Removal.  Tenant shall keep the Leased Premises clean.  Tenant
          ---------------                                                       
shall not burn any materials or rubbish of any description upon the Leased
Premises. Tenant shall keep all accumulated rubbish in covered containers.  In
the event Tenant fails to keep the Leased Premises in the proper condition after
reasonable notice to Tenant, Landlord may cause the same to be done for Tenant
and Tenant shall pay the expenses incurred by Landlord on demand, together with
interest at the Default Rate, as Additional Rent.  Tenant shall, at its sole
cost and expense, comply with all present and future laws, orders and
regulations of all state, county, federal, municipal governments, departments,
commissions and boards regarding the collection, sorting, separation, and
recycling of waste products, garbage, refuse and trash. Tenant shall sort and
separate such waste products, garbage, refuse and trash into such categories as
provided by law.  Each separately sorted category of waste products, garbage,
refuse and trash shall be placed in separate receptacles reasonably approved by
Landlord.  Such separate receptacles may, at Landlord's option, be removed from
the Leased Premises in accordance with a collection schedule prescribed by law.
Landlord reserves the right to refuse to collect or accept from Tenant any waste
products, garbage, refuse or trash that is not separated and sorted as required
by law, and to require Tenant to arrange for such collection at Tenant's sole
cost and expense using a contractor reasonably satisfactory to 

                                       19
<PAGE>
 
Landlord. Tenant shall pay all costs, expenses, fines, penalties or damages that
may be imposed on Landlord or Tenant by reason of Tenant's failure to comply
with the provisions of this Article 20.2, and, at Tenant's sole cost and
                            ------------ 
expense, Tenant shall indemnify, defend and hold Landlord and Landlord's agents
and employees harmless (including reasonable legal fees and expenses) from and
against, and shall be responsible for, all actions, claims, liabilities and
suits arising from such noncompliance, utilizing counsel reasonably satisfactory
to Landlord.

                       21.  SUBORDINATION AND ATTORNMENT
                            ----------------------------

     21.1 Subordination.  This Lease and all rights of Tenant hereunder shall
          -------------                                                      
be, at the option of Landlord, subordinate to  (a) all matters of record, (b)
all ground leases, overriding leases and underlying leases (collectively
referred to as the "leases") of the Building or the Project now or hereafter
                    ------                                                  
existing, (c) all mortgages and deeds of trust (collectively referred to as the
"mortgages") which may now or hereafter encumber or affect the Building or the
 ---------                                                                    
Project, and (d) all renewals, modifications, amendments, replacements and
extensions of leases and mortgages and to spreaders and consolidations of the
mortgages, whether or not leases or mortgages shall also cover other lands,
buildings or leases.  In confirmation of such subordination, Tenant shall
promptly execute, acknowledge and deliver any instrument that Landlord, Superior
Lessor or Superior Mortgagee or any of their respective assigns or successors in
interest may reasonably request to evidence such subordination, provided such
instrument contains nondisturbance language reasonably satisfactory to Tenant.
Prior to the Commencement Date, Landlord will obtain from its existing lender a
subordination, nondisturbance and attornment agreement in form reasonably
acceptable to Tenant and such lender.  Any lease to which this Lease is subject
and subordinate is called a "Superior Lease" and the lessor under a Superior
                             --------------                                 
Lease or its assigns or successors in interest is called a "Superior Lessor".
                                                            ---------------   
Any mortgage to which this Lease is subject and subordinate is called a
                                                                       
"Superior Mortgage" and the holder of a Superior Mortgage is called a 
-------------------
"Superior Mortgagee". If Landlord, a Superior Lessor or a Superior Mortgagee
 ------------------      
requires that such instruments be executed by Tenant, Tenant's failure to do so
within ten (10) business days after request therefor shall be deemed a breach
under this Lease. Tenant waives any right to terminate this Lease because of any
foreclosure proceedings. Notwithstanding anything to the contrary herein, as a
condition to the subordination of Tenant's leasehold interest to a Superior
Lessor or Superior Mortgagee, Landlord shall obtain from any such Superior
Lessor or Superior Mortgagee a subordination, nondisturbance and attornment
agreement in form reasonably satisfactory to Tenant.

     21.2 Attornment.  If any Superior Lessor or Superior Mortgagee (or any
          ----------                                                       
purchaser at a foreclosure sale) succeeds to the rights of Landlord under this
Lease, whether through possession or foreclosure action, or the delivery of a
new lease or deed (a "Successor Landlord"), Tenant shall attorn to and recognize
                      ------------------                                        
such Successor Landlord as Tenant's landlord under this Lease and shall promptly
execute and deliver any instrument that such Successor Landlord may reasonably
request to evidence such attornment.

                           22.  ESTOPPEL CERTIFICATE
                                --------------------

     Tenant shall, whenever requested by Landlord, within twenty (20) days after
written request by Landlord, execute, acknowledge and deliver to Landlord a
statement in writing certifying: (a) that this Lease is unmodified and in full
force and effect, (or, if modified, stating the nature of such modification and
certifying that this Lease, as so modified, is in full force and effect); (b)
the dates to which Annual Basic Rent, Additional Rent and other charges are paid
in advance, if any; (c) that there are not, to Tenant's knowledge, any uncured
defaults on the part of Landlord hereunder or specifying such defaults if any
are claimed; (d) that Tenant has paid Landlord the Security Deposit, (e) the
Commencement Date and the scheduled expiration date of the Lease Term, (f) the
rights (if any) of Tenant to extend or renew this Lease or to expand the Leased
Premises and (g) the amount of Annual Basic Rent, Additional Rent and other
charges currently payable under this Lease.  In addition, such statement shall
provide such other information and facts Landlord may reasonably require.  Any
such statement may be relied upon by any prospective or existing purchaser,
ground lessee or mortgagee of all or any portion of the Project, as well as by
any other assignee of Landlord's interest in this Lease.  Tenant's failure to
deliver such statement within such time shall be conclusive upon Tenant (i) that
this Lease is in full force and effect, without modification except as may be
represented by Landlord; (ii) that there are no uncured defaults in Landlord's
performance hereunder; (iii) that Tenant has paid to Landlord the Security
Deposit; (iv) that not more than one month's installment of Annual Basic Rent or
Additional Rent has been paid in advance; (v) that the Commencement Date and the
scheduled expiration date of the Lease Term are as stated therein, (vii) that
the Annual Basic Rent, Additional Rent and other charges are as set forth
therein, and (viii) that the other information and facts set forth therein are
true and correct.

                                       20
<PAGE>
 
                                   23.  SIGNS
                                        -----

     Landlord shall retain absolute control over the exterior appearance of the
Building and the exterior appearance of the Leased Premises as viewed from the
public halls. Tenant shall  not install, or permit to be installed, any signs,
lettering, advertising, or any items that will in any way, in the reasonable
opinion of Landlord, adversely alter the exterior appearance of the Building or
the exterior appearance of the Leased Premises as viewed from the exterior of
the Building.  Notwithstanding the foregoing, Landlord shall install, at
Tenant's sole cost and expense, letters or numerals at or near the entryway to
the Leased Premises provided Tenant obtains Landlord's prior written consent,
which shall not be unreasonably withheld, as to size, color, design and
location.  All such letters or numerals shall be in accordance with the criteria
reasonably established by Landlord for the Building and uniformly enforced.
Notwithstanding the foregoing, Tenant shall have the right to install the
maximum signage permitted by law on the exterior of the building facing the
Greenway-Hayden loop and the parking lot, subject to the approval of the City of
Scottsdale and Landlord, which consent by Landlord shall not be unreasonably
withheld.  Landlord hereby approves of Tenant's installation of signage as
described in Exhibit "K" hereto.
             -----------        

                                 24.  PARKING
                                      -------

     24.1 Parking Facility.  Landlord shall provide, operate and maintain
          ----------------                                               
parking accommodations (the "Parking Accommodations"), together with necessary
                             ----------------------                           
access, having a capacity adequate in Landlord's opinion to accommodate the
requirements of the Building and the Project.  No storage of vehicles or parking
for more than twenty-four (24) hours shall be allowed without Landlord's prior
written consent.  Tenant acknowledges and agrees that Landlord shall not be
liable for damage, loss or theft of property or injury to persons in, upon or
about the Parking Accommodations from any cause whatsoever.  Landlord shall have
the right to establish, and from time to time change, alter and amend, and to
enforce against all users of the Parking Accommodations, such reasonable
requirements and restrictions as Landlord deems necessary and advisable for the
proper operation and maintenance of the Parking Accommodations, including,
without limitation, designation of particular areas for reserved, visitor and/or
employee parking as a part of the Rules and Regulations of the Building
referenced in Article 31 hereof.
              ----------

     24.2 Parking Spaces.  Tenant is hereby allocated the number of reserved
          --------------                                                    
covered, reserved uncovered and unreserved parking spaces designated in Article
                                                                        -------
11.5 hereof, entitling holders to park in either reserved covered, reserved
----                                                                       
uncovered or unreserved parking spaces, as the case may be, located in the
Parking Accommodations located on the Project adjacent to the Leased Premises as
designated by Landlord from time to time for use by Tenant, its employees and
licensees, and for which Tenant shall pay the monthly charges set forth in
Article 11.6 hereof.  Landlord and Tenant shall execute, prior to the
------------                                                         
Commencement Date a Reserved Covered Parking License in the form attached hereto
as Exhibit "D", and an Unreserved Parking License in the form attached as
   -----------                                                           
Exhibit "F", as applicable.  The unreserved parking spaces shall be available to
-----------                                                                     
Tenant, its employees and licensees on a "first come, first serve" basis.
Holders of parking passes shall not be entitled to park in visitor parking
spaces so designated by Landlord, or in any other parking spaces other than
those designated by Landlord for use by holders of parking passes.

                                  25.  LIENS
                                       -----

     Tenant shall keep the Leased Premises free and clear of all mechanic's and
materialmen's liens.  If, because of any act or omission (or alleged act or
omission) of Tenant, any mechanics', materialmen's or other lien, charge or
order for the payment of money shall be filed or recorded against the Leased
Premises, the Project or the Building, or against any other property of Landlord
(whether or not such lien, charge or order is valid or enforceable as such),
Tenant shall, at its own expense, cause the same to be canceled or discharged of
record within thirty (30) days after Tenant shall have received written notice
of the filing thereof, or Tenant may, within such thirty (30) day period,
furnish to Landlord, a bond pursuant to A.R.S. (S)33-1004 (or any successor
statute) and satisfactory to Landlord and all Superior Lessors and Superior
Mortgagees against the lien, charge or order, in which case Tenant shall have
the right to contest, in good faith, the validity or amount thereof.

                                       21
<PAGE>
 
                               26.  HOLDING OVER
                                    ------------

     It is agreed that the date of termination of this Lease and the right of
Landlord to recover immediate possession of the Leased Premises thereupon is an
important and material matter affecting the parties hereto and the rights of
third parties, all of which have been specifically considered by Landlord and
Tenant.  In the event of any continued occupancy or holding over of the Leased
Premises without the express written consent of Landlord (which may be withheld
by Landlord in its sole and absolute discretion) beyond the expiration or
earlier termination of this Lease or of Tenants right to occupy the Leased
Premises, whether in whole or in part, or by leaving property on the Leased
Premises or otherwise, this Lease shall be deemed a monthly tenancy and Tenant
shall pay one and one half (1 1/2) times the Annual Basic Rent then in effect,
in advance at the beginning of the hold-over month(s), plus any Additional Rent
or other charges or payments contemplated in this Lease, and any other
reasonable costs, expenses, damages, liabilities and attorneys' fees incurred by
Landlord on account of Tenant's holding over.  Landlord shall promptly notify
Tenant of any letter of intent and lease for the Leased Premises.

                             27.  ATTORNEYS' FEES
                                  ---------------

     Tenant shall pay to Landlord all reasonable amounts for costs (including
reasonable attorneys' fees) incurred by Landlord in connection with any breach
or default by Tenant under this Lease.  Such amounts shall be payable within
five (5) days after receipt by Tenant of Landlord's statement.  In addition, if
any action shall be instituted by either of the parties hereto for the
enforcement or interpretation of any of their respective rights or remedies in
or under this Lease, the prevailing party shall be entitled to recover from the
losing party all costs incurred by the prevailing party in such action and any
appeal therefrom, including reasonable attorneys' fees to be fixed by the court.
Further, should Landlord be made a party to any litigation between Tenant and
any third party, then Tenant shall pay all costs and attorneys' fees incurred by
or imposed upon Landlord in connection with such litigation.

                       28.  RESERVED RIGHTS OF LANDLORD
                            ---------------------------

     Landlord reserves the following rights, exercisable without liability to
Tenant for damage or injury to property, persons or business and without
effecting an eviction, constructive or actual, or disturbance of Tenant's use or
possession or giving rise to any claim:


     (a) To name the Building and the Project and to change the name or street
address of the Building or the Project (provided Landlord provides reasonable
notice thereof to Tenant and pays all of Tenant's reasonable costs in connection
therewith);

     (b) To install and maintain all signs, except the Tenant's signs, on the
exterior and interior of the Building and the Project;

     (c) To designate all sources furnishing sign painting and lettering;

     (d) To have pass keys to the Leased Premises and all doors therein,
excluding Tenant's vaults and safes;

     (e) On reasonable prior notice to Tenant, to exhibit the Leased Premises to
any prospective purchaser, mortgagee, or assignee of any mortgage on the
Building or the Project and to others having interest therein at any time during
the Lease Term, and to prospective Tenants during the last six (6) months of the
Lease Term;

     (f) To take any and all measures, including entering the Leased Premises
for the purposes of making inspections, repairs, alterations, additions and
improvements to the Leased Premises or to the Building (including, for the
purposes of checking, calibrating, adjusting and balancing controls and other
parts of the Building systems) as may be necessary or desirable for the
operation, improvement, safety, protection or preservation of the Leased
Premises or the Building, or in order to comply with all laws, orders and
requirements of governmental or other authorities, or as may otherwise be
permitted or required by this Lease; provided, however, that Landlord shall
endeavor (except in an emergency) to minimize interference with Tenant's
business in the Leased Premises;

     (g) To relocate various facilities within the Building and/or the Project
if Landlord shall determine such relocation to be in the best interest of the
development of the Building and/or the Project, provided, that such relocation
shall not materially restrict access to the Leased Premises;

                                       22
<PAGE>
 
     (h) To change the nature, extent, arrangement, use and location of the
Building Common Areas and the Project Common Areas;

     (i) To make alterations or additions to (but not to build additional
stories on) the Building and to build additional buildings or improvements on
the Project; and

     (j) To install vending machines of all kinds in the Leased Premises and the
Building, and to receive all of the revenue derived therefrom, provided,
however, that no vending machines shall be installed by Landlord in the Leased
Premises unless Tenant so requests.

Landlord further reserves the exclusive right to the roof of the Building.  No
easement for light, air, or view is included in the leasing of the Leased
Premises to Tenant. Accordingly, any diminution or shutting off of light, air or
view by any structure which may be erected on the Project or other properties in
the vicinity of the Building shall in no way affect this Lease or impose any
liability upon Landlord.  Notwithstanding anything to the contrary herein,
Landlord shall not exercise any of the foregoing rights to the extent such
exercise would apply discriminatorily to Tenant, unreasonably interfere with
Tenant's use of the Leased Premises or Tenant's parking rights or materially
increase the obligations or decrease the rights of Tenant under this Lease.

                              29.  EMINENT DOMAIN
                                   --------------

     29.1 Taking.  If the whole of the Building is lawfully and permanently
          ------                                                           
taken by condemnation or any other manner for any public or quasi-public
purpose, or by deed in lieu thereof, this Lease shall terminate as of the date
of vesting of title in such condemning authority and the Annual Basic Rent and
Additional Rent shall be pro rated to such date.  If any part of the Building is
so taken, or if the whole of the Building is taken, but not permanently, then
this Lease shall be unaffected thereby, except that (a) Landlord may terminate
this Lease by notice to Tenant within ninety (90) days after the date of vesting
of title in the condemning authority, and (b) if any portion of the Leased
Premises shall be permanently taken and the remaining portion of the Leased
Premises shall not be reasonably sufficient for Tenant to continue operation of
its business, Tenant may terminate this Lease by notice to Landlord within
ninety (90) days after the date of vesting of title in such condemning
authority.  This Lease shall terminate on the thirtieth (30th) day after receipt
by Landlord of such notice, by which date Tenant shall vacate and surrender the
Leased Premises to Landlord.  The Annual Basic Rent and Additional Rent shall be
pro rated to the earlier of the termination of this Lease or such date as Tenant
is required to vacate the Leased Premises by reason of the taking. If this Lease
is not terminated as a result of a partial taking of the Leased Premises, the
Annual Basic Rent and Additional Rent shall be equitably adjusted according to
the rentable area of the Leased Premises and Building remaining.

     29.2 Award.  In the event of a taking of all or any part of the Building or
          -----                                                                 
the Project, all of the proceeds or the award, judgment, settlement or damages
payable by the condemning authority shall be and remain the sole and exclusive
property of Landlord, and Tenant hereby assigns all of its right, title and
interest in and to any such award, judgment, settlement or damages to Landlord.
Tenant shall, however, have the right, to the extent that the same shall not
reduce or prejudice amounts properly payable to Landlord, to claim from the
condemning authority, but not from Landlord, such compensation as may be
recoverable by Tenant in its own right for relocation benefits, moving expenses,
and damage to Tenant's personal property and trade fixtures.

                                  30.  NOTICES
                                       -------

     Any notice or communication given under the terms of this Lease shall be in
writing and shall be delivered in person, sent by any public or private express
delivery service or deposited with the United States Postal Service or a
successor agency, certified or registered mail, return receipt requested,
postage pre-paid, addressed as set forth in the Basic Provisions, or at such
other address as a party may from time to time designate by notice hereunder.
Notice shall be effective upon delivery.  The inability to deliver a notice
because of a changed address of which no notice was given or a rejection or
other refusal to accept any notice shall be deemed to be the receipt of the
notice as of the date of such inability to deliver or rejection or refusal to
accept.  Any notice to be given by Landlord may be given by the legal counsel
and/or the authorized agent of Landlord.

                                       23
<PAGE>
 
                           31.  RULES AND REGULATIONS
                                ---------------------

     Tenant shall abide by all rules and regulations (the "Rules and
                                                           ---------
Regulations") of the Building and the Project imposed by Landlord, as attached
hereto as Exhibit "I" or as may hereafter be issued by Landlord. Such Rules and
          -----------                                                          
Regulations are imposed to enhance the cleanliness, appearance, maintenance,
order and use of the Leased Premises, the Building and the Project, and the
proper enjoyment of the Building and the Project by all tenants and their
clients, customers and employees.  The Rules and Regulations may be changed from
time to time upon ten (10) days notice to Tenant.  Breach of the Rules and
Regulations, by Tenant shall constitute an Event of Default if such breach is
not fully cured within the applicable cure period after written notice to Tenant
by Landlord. Landlord shall not be responsible to Tenant for nonperformance by
any other tenant, occupant or invitee of the Building or the Project of any
Rules or Regulations.  Notwithstanding the foregoing, Tenant shall not be
required to comply with any new rule or regulation unless the same applies non-
discriminatorily to all occupants of the Project, does not unreasonably
interfere with Tenant's use of the Leased Premises or Tenant's parking rights
and does not materially increase the obligations or decrease the rights of
Tenant under this Lease.

                          32.  ACCORD AND SATISFACTION
                               -----------------------

     No payment by Tenant or receipt by Landlord of a lesser amount than the
monthly installment of Annual Base Rent and Additional Rent (jointly called
"Rent" in this Article 32), shall be deemed to be other than on account of the
-----          ----------                                                     
earliest stipulated Rent due and not yet paid, nor shall any endorsement or
statement on any check or any letter accompanying any check or payment as Rent
be deemed an accord and satisfaction. Landlord may accept such check or payment
without prejudice to Landlord's right to recover the balance of such Rent or to
pursue any other remedy in this Lease.  No receipt of money by Landlord from
Tenant after the termination of this Lease, after the service of any notice
relating to the termination of this Lease, after the commencement of any suit,
or after final judgment for possession of the Leased Premises, shall reinstate,
continue or extend the Lease Term or affect any such notice, demand, suit or
judgment.

                           33.  BANKRUPTCY OF TENANT
                                --------------------

     33.1 Chapter 7.  If a petition is filed by, or an order for relief is
          ---------                                                       
entered against Tenant under Chapter 7 of the Bankruptcy Code and the trustee of
Tenant elects to assume this Lease for the purpose of assigning it, the election
or assignment, or both, may be made only if all of the terms and conditions of
                                                                              
Articles 33.2 and 33.4 below are satisfied.  If the trustee fails to elect to
----------------------                                                       
assume this Lease for the purpose  of assigning it within sixty (60) days after
appointment, this Lease will be deemed to have been rejected.  To be effective,
an election to assume this Lease must be in writing and addressed to Landlord
and, in Landlord's business judgment, all of the conditions hereinafter stated,
which Landlord and Tenant acknowledge to be commercially reasonable, must have
been satisfied. Landlord shall then immediately be entitled to possession of the
Premises without further obligation to Tenant or the trustee, and this Lease
will be terminated. Landlord's right to be compensated for damages in the
bankruptcy proceeding, however, shall survive.

     33.2 Chapters 11 and 13.  If Tenant files a petition for reorganization
          ------------------                                                
under Chapters 11 or 13 of the Bankruptcy Code or a proceeding that is filed by
or against Tenant under any other chapter of the Bankruptcy Code is converted to
a Chapter 11 or 13 proceeding and Tenant's trustee or Tenant as a debtor-in-
possession fails to assume this Lease within sixty (60) days from the date of
the filing of the petition or the conversion, the trustee or the debtor-in-
possession will be deemed to have rejected this Lease.  To be effective, an
election to assume this Lease must be in writing and addressed to Landlord and,
in Landlord's business judgment, all of the following conditions, which Landlord
and Tenant acknowledge to be commercially reasonable, must have been satisfied:

          (a) The trustee or the debtor-in-possession has cured or has provided
to Landlord adequate assurance, as defined in this Article 33.2, that;
                                                   ------------       

                (1) The trustee will cure all monetary defaults under this Lease
within a reasonable period from the date of the assumption; and

                (2) The trustee will cure all non-monetary defaults under this
Lease within a reasonable period from the date of the assumption.

          (b) The trustee or the debtor-in-possession has compensated Landlord,
or has provided to Landlord adequate assurance, as defined in this Article 33.2,
                                                                   ------------ 
that within a reasonable period from the date of 

                                       24
<PAGE>
 
the assumption Landlord will be compensated for any pecuniary loss it incurred
arising from the default of Tenant, the trustee, or the debtor-in-possession as
recited in Landlord's written statement of pecuniary loss sent to the trustee or
the debtor-in-possession. For purposes of this Lease, pecuniary loss shall
include all reasonable attorneys' fees and court costs incurred by Landlord in
connection with any bankruptcy proceeding filed by or against Tenant.

          (c) The trustee or the debtor-in-possession has provided Landlord with
adequate assurance of the future performance of each of Tenant's obligations
under the Lease; provided, however, that:

                (1) The trustee or debtor-in-possession will also deposit with
Landlord as security for the timely payment of Annual Basic Rent and Additional
Rent, an amount equal to three months Annual Basic Rent and Additional Rent
accruing under this Lease.

                (2) If not otherwise required by the terms of this Lease, the
trustee or the debtor-in-possession will also pay in advance, on each day that
the Annual Basic Rent is payable, one-twelfth of Tenant's estimated annual
obligations under the Lease for the Additional Rent.

                (3) From and after the date of the assumption of this Lease, the
trustee or the debtor-in-possession will pay the Annual Basic Rent and
Additional Rent as provided in Article 5 above.
                               ---------       

                (4) The obligations imposed upon the trustee or the debtor-in-
possession will continue for Tenant after the completion of bankruptcy
proceedings.

          (d) Landlord has determined that the assumption of the Lease will not:

                (1) Breach any provisions in any other lease, mortgage,
financing agreement, or other agreement by which Landlord is bound relating to
the Project; or

                (2) Disrupt, in Landlord's judgment, the tenant mix of the
Building or the Project or any other attempt by Landlord to provide a specific
variety of Tenants in the Building or the Project that, in Landlord's judgment,
would be most beneficial to all of the tenants of the Building and the Project
and would enhance the image, reputation, and profitability of the Building and
the Project.

          (e) For purposes of this Article 33.2 "adequate assurance" means that:
                                   ------------  ------------------             

                (1) Landlord will determine that the trustee or the debtor-in-
possession has, and will continue to have, sufficient unencumbered assets after
the payment of all secured obligations and administrative expenses to assure
Landlord that the trustee or the debtor-in-possession will have sufficient funds
to fulfill Tenant's obligations under this Lease and to keep the Leased Premises
properly staffed with sufficient employees to conduct a fully operational,
actively promoted business on the Leased Premises; and

                (2) An order will have been entered segregating sufficient cash
payable to Landlord and/or a valid and perfected first lien and security
interest will have been granted in property of Tenant, trustee, or debtor-in-
possession that is acceptable for value and kind to Landlord, to secure to
Landlord the obligation of the trustee or debtor-in-possession to cure the
monetary or non-monetary defaults under this Lease within the time periods set
forth above.

     33.3 Landlord's Right to Terminate.  In the event that this Lease is
          -----------------------------                                  
assumed by a trustee appointed for Tenant or by Tenant as debtor-in-possession
under the provisions of Article 33.2 above and, thereafter, Tenant is either
                        ------------                                        
adjudicated a bankrupt or files a subsequent petition for arrangement under
chapter 11 of the Bankruptcy Code, then Landlord may terminate, at its option,
this Lease and all Tenant's rights under it, by giving written notice of
Landlord's election to terminate.

     33.4 Assignment by Trustee.  If the trustee or the debtor-in-possession has
          ---------------------                                                 
assumed the Lease, under the terms of Article 33.1 or 33.2 above, and elects to
                                      --------------------                     
assign Tenant's interest under this Lease or the estate created by that interest
to any other person, that interest or estate may be assigned only if Landlord
acknowledges in writing that the intended assignee has provided adequate
assurance, as defined in this Article 33.4, of future performance of all of the
                              ------------                                     
terms, covenants, and conditions of this Lease to be performed by Tenant.

     33.5 Adequate Assurance.  For the purposes of this Article 33 "adequate
          ------------------                            ----------  --------
assurance of future performance" means that Landlord has ascertained that each
-------------------------------                                               
of the following conditions has been satisfied:

                                       25
<PAGE>
 
          (1) The assignee has submitted a current financial statement, audited
by a certified public accountant, that shows a net worth and working capital in
amounts determined by Landlord to be sufficient to assure the future performance
by the assignee of Tenant's obligations under this Lease;

          (2) If requested by Landlord, the assignee will obtain guarantees, in
form and substance satisfactory to Landlord from one or more persons who satisfy
Landlord's standards of creditworthiness;

          (3) Landlord has obtained all consents or waivers from any third party
required under any lease, mortgage, financing arrangement or other agreement by
which Landlord is bound, to enable Landlord to permit the assignment;

          (4) When, pursuant to the Bankruptcy Code, the trustee or the debtor-
in-possession is obligated to pay reasonable use and occupancy charges for the
use of all or part of the Leased Premises, the charges will not be less than the
Annual Basic Rent and Additional Rent.

     33.6 Consent of Landlord.  Neither Tenant's interest in the Lease nor any
          -------------------                                                 
estate of Tenant created in the Lease will pass to any trustee, receiver,
assignee for the benefit of creditors, or any other person or entity, or
otherwise by operation of law under the laws of any state having jurisdiction of
the person or property of Tenant unless Landlord consents in writing to the
transfer.  Landlord's acceptance of Annual Basic Rent or Additional Rent or any
other payments from any trustee, receiver, assignee, person, or other entity
will not be deemed to have waived, or waive, the need to obtain Landlord's
consent or Landlord's right to terminate this Lease for any transfer of Tenant's
interest under this Lease without that consent.

                           34.  HAZARDOUS MATERIALS
                                -------------------

     34.1 Hazardous Materials Laws.  "Hazardous Materials Laws" means any and
          ------------------------    ------------------------               
all federal, state or local laws, ordinances, rules, decrees, orders,
regulations or court decisions (including the so-called "common-law") relating
                                                         ----------           
to hazardous substances, hazardous materials, hazardous waste, toxic substances,
environmental conditions on, under or about the Premises, or soil and ground
water conditions, including, but not limited to, the Comprehensive Environmental
Response, Compensation and Liability Act of 1980 ("CERCLA"), as amended, 42
                                                   ------                  
U.S.C. (S)9601, et seq., the Resource Conversation and Recovery Act ("RCRA"), 42
                                                                      ----      
U.S.C. (S)6901, et seq., the Hazardous Materials Transportation Act, 49 U.S.C.
(S)1801, et seq., any amendments to the foregoing, and any similar federal,
state or local laws, ordinances, rules, decrees, orders or regulations.

     34.2 Hazardous Materials.  "Hazardous Materials" means any chemical,
          -------------------    -------------------                     
compound, material, substance or other matter that: (i) is a flammable
explosive, asbestos, radioactive material, nuclear medicine material, drug,
vaccine, bacteria, virus, hazardous waste, toxic substance, petroleum product,
or related injurious or potentially injurious material, whether injurious or
potentially injurious by itself or in combination with other materials; (ii) is
controlled, designated in or governed by any Hazardous Materials Law; (iii)
gives rise to any reporting, notice or publication requirements under any
Hazardous Materials Law; or (iv) gives rise to any liability, responsibility or
duty on the part of Tenant or Landlord with respect to any third person under
any Hazardous Materials Law.

     34.3 Use.  Tenant and its agents, employees, contractors and invitees shall
          ---                                                                   
not use, generate, release, store, bring onto or otherwise dispose of, on, under
or about, or transport from, the Leased Premises, the Building or the Project,
any Hazardous Materials unless: (a) such use is specifically disclosed to and
approved by Landlord in writing prior to such use, (b) such use is conducted in
compliance with the provisions of this Article 34, or (c) such use is of normal
                                       ----------                              
amounts of Hazardous Materials normally found in general office uses and used in
accordance with all Hazardous Materials Laws.  Landlord may approve such use
subject to reasonable conditions to protect the Leased Premises, the Building or
the Project, and Landlord's interests.  Landlord may withhold approval if
Landlord determines that such proposed use involves a material risk of a release
or discharge of Hazardous Materials or a violation of any Hazardous Materials
Laws or that Tenant has not provided reasonable assurances of its ability to
remedy such a violation and fulfill its obligations under this Article 34.
                                                               ---------- 

     34.4 Compliance With Laws.  Tenant shall strictly comply with all Hazardous
          --------------------                                                  
Materials Laws.  Tenant shall obtain and maintain in full force and effect all
permits, licenses and other governmental approvals required for Tenant's
operations on the Leased Premises under any Hazardous Materials Laws and shall
comply with all terms and conditions thereof.  At Landlord's request, Tenant
shall deliver copies 

                                       26
<PAGE>
 
of, or allow Landlord to inspect, all such permits, licenses and approvals.
Tenant shall perform any monitoring, investigation, clean-up, removal and other
remedial work (collectively, "Remedial Work") required as a result of any
                              -------------  
release or discharge of Hazardous Materials affecting the Leased Premises, the
Building or the Project, or any violation of Hazardous Materials Laws in any
such case by Tenant or any assignee or sublessee of Tenant or their respective
agents, contractors, employees, licensees, or invitees. Landlord shall have the
right to intervene in any governmental action or proceeding involving any
Remedial Work, and to approve performance of the work, in order to protect
Landlord's interests.

     34.5 Compliance With Insurance Requirements.  Tenant shall comply with the
          --------------------------------------                               
requirements of Landlord's and Tenant's respective insurers regarding Tenant's
use of Hazardous Materials and with such insurers' recommendations based upon
prudent industry practices regarding management of Hazardous Materials.

     34.6 Notice; Reporting.  Tenant shall notify Landlord, in writing, within
          -----------------                                                   
two (2) days after any of the following: (a) Tenant's knowledge of a release or
discharge of any Hazardous Material, whether or not the release or discharge is
in quantities that would otherwise be reportable to a public agency; (b)
Tenant's receipt of any order of a governmental agency requiring any Remedial
Work pursuant to any Hazardous Materials Laws; (c) Tenant's receipt of any
warning, notice of inspection, notice of violation or alleged violation, or
Tenant's receipt of notice or knowledge of any proceeding, investigation of
enforcement action, pursuant to any Hazardous Materials Laws; or (d) Tenant's
receipt of notice or knowledge of any claims made or threatened by any third
party against Tenant or the Leased Premises, the Building or the Project,
relating to any loss or injury resulting from Hazardous Materials.  Tenant shall
deliver to Landlord copies of all test results, reports and business or
management plans required to be filed with any governmental agency pursuant to
any Hazardous Materials Laws.

     34.7 Termination; Expiration.  Upon the termination or expiration of this
          -----------------------                                             
Lease, Tenant shall remove any equipment, improvements or storage facilities
utilized by Tenant in connection with any Hazardous Materials used by Tenant and
shall, clean up, detoxify, repair and otherwise restore the Leased Premises to a
condition free of Hazardous Materials used by Tenant, to the extent required by
Hazardous Materials Laws.

     34.8 Indemnity.  Tenant shall protect, indemnify, defend and hold Landlord
          ---------                                                            
harmless from and against, and shall be responsible for, any and all claims,
costs, expenses, suits, judgments, actions, investigations, proceedings and
liabilities arising out of or in connection with any breach of any provisions of
this Article 34 or directly or indirectly arising out of the use, generation,
     ----------                                                              
storage, release, disposal or transportation of Hazardous Materials by Tenant or
any sublessee or assignee of Tenant, or their respective agents, contractors,
employees, licensees, or invitees, on, under or about the Leased Premises, the
Building or the Project during the Lease Term or Tenant's occupancy of the
Leased Premises in violation of applicable laws or this Lease, including, but
not limited to, all foreseeable and unforeseeable consequential damages and the
cost of any Remedial Work. The consent by Landlord to the use, generation,
storage, release, disposal or transportation of Hazardous Materials shall not
excuse Tenant from Tenant's indemnification obligations pursuant to this Article
                                                                         -------
34. The foregoing indemnity, as to Hazardous Materials only, shall be in lieu of
--
the indemnification provisions of Article 16 of this Lease. Tenant's and
                                  ----------
Landlord's obligations pursuant to this Article 34 shall survive the termination
                                        ---------- 
or expiration of this Lease. To the actual knowledge of Landlord, without
inquiry or the duty to inquire, (a) no Hazardous Material is present on the
Project or the soil, surface water or groundwater thereof, (b) no underground
storage tanks are present on the Project, and (c) no action, proceeding or claim
is pending or threatened regarding the Project concerning any Hazardous Material
or pursuant to any Hazardous Materials Laws. Under no circumstance shall Tenant
be liable for, and Landlord shall release Tenant, its agents, contractors,
stockholders, directors, successors, representatives, and assigns for, from and
against all losses, costs, claims, liabilities and damages (including attorneys'
fees and consultants' fees) of every type and nature, directly or indirectly
arising out of or in connection with any Hazardous Material present at any time
on or about the Project, or the soil, air, improvements, groundwater or surface
water thereof, or in violation of any laws, orders or regulations, relating to
any such Hazardous Material, except to the extent that any of the foregoing
results from Tenant's or its agents', employees', contractors' or invitees'
discharge, release, use, transporting or disposal of Hazardous Materials. The
indemnity in this Article 34 constitutes the entire agreement of Landlord and
                  ----------  
Tenant regarding indemnification for Hazardous Materials. No other provision of
this Lease shall be deemed to apply thereto.

     34.9 Assignment; Subletting.  If Landlord's consent is required for an
          ----------------------                                           
assignment of this Lease or a subletting of the Leased Premises, Landlord shall
have the right to refuse such consent if the possibility of a release of
Hazardous Materials is substantial as a result of the assignment or sublease or
if Landlord does not receive reasonable assurances that the new tenant has the
experience and the financial ability to 

                                       27
<PAGE>
 
remedy a violation of the Hazardous Materials Laws and fulfill its obligations
under this Article 34.
           ---------- 

     34.10  Entry and Inspection; Cure.  Landlord and its agents, employees and
            --------------------------                                         
contractors, shall have the right, but not the obligation, to enter the Leased
Premises at all reasonable times to inspect the Leased Premises and Tenant's
compliance with the terms and conditions of this Article 34, or to conduct
                                                 ----------               
investigations and tests.  No prior notice to Tenant shall be required in the
event of an emergency, or if Landlord has reasonable cause to believe that
violations of this Article 34 have occurred, or if Tenant consents at the time
                   ----------                                                 
of entry.  In all other cases, Landlord shall give at least twenty-four (24)
hours prior notice to Tenant.  Landlord shall have the right, but not the
obligation, to remedy any violation by Tenant of the provisions of this Article
                                                                        -------
34 or to perform any Remedial Work related to Tenant's or its agents',
--                                                                    
employees', contractors' or invitees' use of Hazardous Materials which is
necessary or appropriate as a result of any governmental order, investigation or
proceeding.  Tenant shall pay, upon demand, as Additional Rent, all costs
incurred by Landlord in remedying such violations or performing all such
Remedial Work, plus interest thereon at the Default Rate from the date of demand
until the date received by Landlord.

     34.11  Event of Default.  The release or discharge of any Hazardous
            ----------------                                            
Material or the violation of any Hazardous Materials Law shall constitute a
default by Tenant under this Lease.  In addition to and not in lieu of the
remedies available under this Lease as a result of such Event of Default,
Landlord shall have the right, without terminating this Lease, to require Tenant
to suspend its operations and activities on the Leased Premises until Landlord
is satisfied that appropriate Remedial Work has been or is being adequately
performed and Landlord's election of this remedy shall not constitute a waiver
of Landlord's right thereafter to pursue the other remedies set forth in this
Lease.

                              35.  MISCELLANEOUS
                                   -------------

     35.1 Entire Agreement, Amendments.  This Lease and any Exhibits and Riders
          ----------------------------                                         
attached hereto and forming a part hereof, set forth all of the covenants,
promises, agreements, conditions and understandings between Landlord and Tenant
concerning the Leased Premises and there are no covenants, promises, agreements,
representations, warranties, conditions or understandings either oral or written
between them other than as contained in this Lease.  Except as otherwise
provided in this Lease, no subsequent alteration, amendment, change or addition
to this Lease shall be binding unless it is in writing and signed by both
Landlord and Tenant.

     35.2 Time of the Essence.  Time is of the essence of each and every term,
          -------------------                                                 
covenant and condition of this Lease.

     35.3 Binding Effect.  The covenants and conditions of this Lease shall,
          --------------                                                    
subject to the restrictions on assignment and subletting, apply to and bind the
heirs, executors, administrators, personal representatives, successors and
assigns of the parties hereto.

     35.4 Recordation.  Neither this Lease nor any memorandum hereof shall be
          -----------                                                        
recorded by Tenant.  At the sole option of Landlord, Tenant and Landlord shall
execute, and Landlord may record, a short form memorandum of this Lease in form
and substance satisfactory to Landlord.

     35.5 Governing Law.  This Lease and all the terms and conditions thereof
          -------------                                                      
shall be governed by and construed in accordance with the laws of the State of
Arizona.

     35.6 Defined Terms and Paragraph Headings.  The words "Landlord" and
          ------------------------------------              --------     
"Tenant" as used in this Lease shall include the plural as well as the singular.
-------
Words used in masculine gender  include the feminine and neuter.  If there is
more than one Tenant, the obligations in this Lease imposed upon Tenant shall be
joint and several.  The paragraph headings and titles to the paragraphs of this
Lease are not a part of this Lease and shall have no effect upon the
construction or interpretation of any part hereof.

     35.7 Representations and Warranties of Tenant.  Tenant represents and
          ----------------------------------------                        
warrants to Landlord as follows:

          (a) Tenant has been duly organized, is validly existing, and is in
good standing under the laws of its State of Delaware and is qualified to
transact business in Arizona.  All necessary action on the part of Tenant has
been taken to authorize the execution, delivery and performance of this Lease
and of the other documents, instruments and agreements, if any, provided for
herein.  The persons who have executed this Lease on behalf of Tenant are duly
authorized to do so;

          (b) This Lease constitutes the legal, valid and binding obligation of
Tenant, 

                                       28
<PAGE>
 
enforceable against Tenant in accordance with its terms, subject, however, to
bankruptcy, insolvency, reorganization, arrangement, moratorium or other similar
laws relating to or affecting the rights of creditors generally, general
principles of equity, whether enforceability is considered in a proceeding in
equity or at law, and to the qualification that certain waivers, procedures,
remedies and other provisions of this Lease may be unenforceable under or
limited by applicable law, however, none of the foregoing shall prevent the
practical realization to Landlord of the benefits intended by this Lease; and

          (c) To the best of its knowledge, Tenant is not, and the execution,
delivery and performance of this Lease and the documents, instruments and
agreements, if any, provided for herein will not result in any breach of or
default under any other document, instrument or agreement to which Tenant is a
party or by which Tenant is subject or bound, that would have a material adverse
effect on Tenant's ability to perform its obligations hereunder.

     35.8 No Waiver.  The failure of either party to insist in any one or more
          ---------                                                           
instances upon the strict performance of any one or more of the obligations of
this Lease, or to exercise any election herein contained, shall not be construed
as a waiver or relinquishment for the future of the performance of such one or
more obligations of this Lease or the right to exercise such election, but the
same shall continue and remain in full force and effect with respect to any
subsequent breach, act or omission.

     35.9 Severability.  If any clause or provision of this Lease is or becomes
          ------------                                                         
illegal or unenforceable because of any present or future law or regulation of
any governmental body or entity effective during the Lease Term, the intention
of the parties is that the remaining provisions of this Lease shall not be
affected thereby.

     35.10  Exhibits.  If any provision contained in an Exhibit, Rider or
            --------                                                     
Addenda to this Lease is inconsistent with any other provision of this Lease,
the provision contained in this Lease shall supersede the provisions contained
in such Exhibit, Rider or Addenda, unless otherwise provided.

     35.11  Fair Meaning.  The language of this Lease shall be construed to its
            ------------                                                       
normal and usual meaning and not strictly for or against either Landlord or
Tenant.  Landlord and Tenant acknowledge and agree that each party has reviewed
and revised this Lease and that any rule of construction to the effect that
ambiguities are to be resolved against the drafting party shall not apply to the
interpretation of this Lease, or any Exhibits, Riders or amendments hereto.

     35.12  No Merger.  The voluntary or other surrender of this Lease by Tenant
            ---------                                                           
or a mutual cancellation of this Lease shall not work as a merger and shall, at
Landlord's option, either terminate any or all existing subleases or
subtenancies, or operate as an assignment to Landlord of any or all of such
subleases or subtenancies.

     35.13  Force Majeure.  Any prevention, delay or stoppage due to strikes,
            -------------                                                    
lockouts, labor disputes, acts of God, inability to obtain labor or materials
for reasonable substitutes therefor, governmental restrictions, regulations or
controls, judicial orders, enemy or hostile government actions, civil commotion,
fire or other casualty and other causes beyond the reasonable control of
Landlord shall excuse the Landlord's performance hereunder for the period of any
such prevention, delay, or stoppage.

     35.14  Government Energy or Utility Controls.  In the event of the
            -------------------------------------                      
imposition of federal, state or local governmental controls, rules, regulations
or restrictions on the use or consumption of energy or other utilities during
the Lease Term, both Landlord and Tenant shall be bound thereby.  In the event
of a difference in interpretation of any governmental control, rule, regulation
or restriction between Landlord and Tenant, the interpretation of Landlord shall
prevail, and Landlord shall have the right to enforce compliance, including the
right of entry into the Leased Premises to effect compliance.

     35.15  Shoring.  If any excavation or construction is made adjacent to,
            -------                                                         
upon or within the Building, or any part thereof, Tenant shall afford to any and
all persons causing or authorized to cause such excavation or construction
license to enter onto the Leased Premises for the purpose of doing such work as
such persons shall deem necessary to preserve the Building or any portion
thereof from injury or damage and to support the same by proper foundations,
braces and supports without any claim for damages, indemnity or abatement of
Annual Basic Rent or Additional Rent or for a constructive or actual eviction of
Tenant.  Such entry shall be subject to the provisions of Article 17 hereof.
                                                          ----------        

     35.16  Transfer of Landlord's Interest.  The term "Landlord" as used in
            -------------------------------             --------            
this Lease, insofar as the covenants or agreements on the part of the Landlord
are concerned, shall be limited to mean and include only the owner or owners of
Landlord's interest in this Lease at the time in question.  Upon any transfer or

                                       29
<PAGE>
 
transfers of such interest, the Landlord herein named (and in the case of any
subsequent transfer, the then transferor) shall thereafter be relieved of all
liability for the performance of any covenants or agreements on the part of the
Landlord contained in this Lease to be performed thereafter, provided any
transferees assume in writing future obligations of Landlord hereunder.

     35.17  Limitation on Landlord's Liability.  If Landlord becomes obligated
            ----------------------------------                                
to pay Tenant any judgment arising out of any failure by the Landlord to perform
or observe any of the terms, covenants, conditions or provisions to be performed
or observed by Landlord under this Lease, Tenant shall be limited in the
satisfaction of such judgment solely to Landlord's interest in the Building and
the Project or any proceeds arising from the sale thereof and no other property
or assets of Landlord or the individual partners, directors, officers or
shareholders of Landlord or its constituent partners shall be subject to levy,
execution or other enforcement procedure whatsoever for the satisfaction of any
such money judgment.

     35.18  Brokerage Fees.  Tenant warrants and represents that it has not
            --------------                                                 
dealt with any realtor, broker or agent in connection with this Lease except the
Broker identified in Article 11.8 above. Tenant shall indemnify, defend and hold
                     ------------
Landlord harmless from and against, and shall be responsible for, any cost,
expense or liability (including the cost of suit and reasonable attorneys' fees)
for any compensation, commission or charges claimed by any other realtor, broker
or agent in connection with this Lease or by reason of any act of Tenant.

     35.19  Continuing Obligations.  All obligations of Landlord and Tenant
            ----------------------                                         
hereunder not fully performed as of the expiration or earlier termination of
this Lease shall survive the expiration or earlier termination of this Lease,
including, without limitation, all payment obligations with respect to Annual
Basic Rent, Additional Rent and all obligations concerning the condition of the
Premises.

     35.20  Reasonable Consents.  Whenever this Lease requires an approval,
            -------------------                                            
consent, determination or judgment by either Landlord or Tenant, unless another
standard is expressly set forth, such approval, consent, determination or
judgment shall be reasonable and shall not be unreasonably withheld or delayed.
Any expenditure by a party permitted or required under this Lease, for which
such party demands reimbursement, shall be reasonably incurred, and shall be
substantiated by documentary evidence available for inspection and review by the
other party.


     IN WITNESS WHEREOF, Landlord and Tenant have executed this Lease as of the
date and year first above written.

                              LANDLORD:

                              SEOC I Limited Partnership, an Arizona limited
                              partnership

                              By:   Cavan Investments, Ltd., an Arizona
                                    corporation, its General Partner



                                    By:  /s/ David V. Cavan
                                       --------------------------------------
                                    Name:    David V. Cavan
                                       --------------------------------------
                                    Its:     President
                                       --------------------------------------

                                       30
<PAGE>
 
                              TENANT:

                              CBT SYSTEMS USA, LTD., a Delaware corporation



                              By:  /s/ James J. Buckley
                                 ---------------------------------------- 
                              Name:    James J. Buckley
                                   -------------------------------------- 
                              Its:     President & CEO
                                  --------------------------------------- 

Witness for purposes of
Power of Attorney:


                              By:  /s/ Gregory M. Priest
Witness  /s/ Greg Porto          ----------------------------------------
Name:    Greg Porto           Name:    Gregory M. Priest
                                   --------------------------------------
                              Its: VP, Finance, CFO & Assistant Secretary
                                  --------------------------------------- 

If Tenant is a CORPORATION, the 
               -----------             
authorized officers must sign on 
behalf of the corporation and 
indicate the capacity in which 
they are signing.  The Lease must
be executed by the president or 
vice president and the secretary 
               ---
or assistant secretary, unless the 
                        ------
bylaws or a resolution of the 
board of directors shall otherwise 
provide, in which event, the bylaws 
or a certified copy of the resolution, 
as the case may be, must be attached 
to this Lease.

                                       31
<PAGE>
 
                                   RIDER "1"
                                   ---------

     Rider 1 to Lease dated December 31, 1997, between SEOC I LIMITED
     PARTNERSHIP, an Arizona limited partnership ("Landlord"), and CBT SYSTEMS
                                                   --------                   
     USA, LTD., a Delaware corporation ("Tenant").
                                         ------   


     1.   Option to Extend.  Provided that an Event of Default does not then
          ----------------                                                  
exist at the time of exercise, then Tenant shall have, and is hereby granted,
the option to extend the Initial Term for one (1) additional period of five (5)
years.  Except as set forth in Section 2 of this Rider, Tenant's occupancy of
                               ---------                                     
the Leased Premises during the Renewal Term shall be governed by all of the
terms, conditions, covenants and provisions of the Lease to which this Rider is
attached except that Tenant shall have no further option to extend the Initial
Term after the expiration of the Renewal Term.  If Tenant desires to exercise
its option to extend the Initial Term, it must give Landlord notice in writing
("Option Notice") of its intent to do so at least nine (9) months, but not more
  -------------                                                                
than twenty-four (24) months prior to the expiration of the Initial Term.  For
the purposes of the Lease to which this Rider is attached, the phrase "Lease
                                                                       -----
Term" shall be deemed to refer to  the Initial Term and the Renewal Term to the
----                                                                           
extent applicable.

     2.   Amendment to Basic Provisions.  In the event Tenant exercises such
          -----------------------------                                     
option to extend, the following terms shall apply:

          (a) Lease Term.  Article 1.10 of the Lease entitled "Lease Term" is
              ----------   ------------                        ----------    
hereby deleted and replaced with the following:

              1.10 Lease Term.
                   ---------- 

                   (a) Initial Term:  Five (5) years and one (1) month;
                       ------------                                    

                   (b)  Renewal Term:  Five (5) years.
                        ------------                  

          (b) Annual Basic Rent.  Article 1.12 of the Lease entitled "Annual
              -----------------   ------------                        ------
Basic Rent" is hereby deleted and replaced with the following:
----------                                                    

              1.12  Annual Basic Rent.
                    ----------------- 

                    (a) Initial Term:  LEASE MONTH 1:  No charge for Basic Rent;
LEASE MONTHS 2-37: $30,898.29 per month based upon a rental rate of $14.50 per
rentable square foot; LEASE MONTHS 38-61: $32,496.48 per month based upon a
rental rate of $15.25 per rentable square foot. Landlord and Tenant shall have
fifteen (15) business days after Landlord receives the Option Notice within
which to agree on the Annual Basic Rental for the Renewal Term based upon the
"THEN FAIR MARKET RENTAL VALUE OF THE PREMISES" as defined below. If the
----------------------------------------------                           
parties agree on the Annual Basic Rental for the Renewal Term within fifteen
(15) business days, they shall amend this Lease by stating the Annual Basic
Rental for the Renewal Term.

                    (b) If they are unable to agree on the Annual Basic Rental
for the Renewal Term within the fifteen (15) business day period, then the
Annual Basic Rental shall be the "THEN FAIR MARKET RENTAL VALUE OF THE PREMISES"
                                  ---------------------------------------------
as determined in accordance with this Rider.

                    (c) The "THEN FAIR MARKET RENTAL VALUE OF THE PREMISES" 
                             ---------------------------------------------
means what a landlord under no compulsion to lease the Premises and a tenant
under no compulsion to lease the Premises, would determine as rent for the
Renewal Term, as of the commencement of the Renewal Term, taking into
consideration the use permitted under the Lease, the quality, size, shape,
design and location of the Premises within the Building and the location of the
Building.

                    (d) Within seven (7) business days after the expiration of
the fifteen (15) business day period set forth in Subsection 1.13 above,
Landlord and Tenant shall each appoint a real estate appraiser with at least
five (5) full years full-time commercial appraisal experience in the area in
which the Premises are located to appraise the then fair market rental value of
the Premises. If either the Landlord or the Tenant does not appoint an appraiser
within ten (10) days after the other has given notice of the name of its
appraiser, the single appraiser appointed shall be the sole appraiser and shall
set the then fair market rental value of the Premises. If two (2) appraisers are
appointed pursuant to this paragraph, they shall meet promptly and attempt to
set the then fair market rental value of the Premises. If they are unable to
agree within the thirty (30) days after the second appraiser has been appointed,
they shall attempt to elect 

                                   Rider 1-1
<PAGE>
 
a third appraiser meeting the qualifications stated in this paragraph within ten
(10) days after the last day the two (2) appraisers are given to set the then
fair market rental value of the Premises. If they are unable to agree on the
third appraiser, either the Landlord or Tenant may petition the presiding civil
court judge of the Maricopa County Superior Court for the selection of a third
appraiser who meets the qualifications stated in this paragraph. Each party
shall pay the cost of its own appraiser and one half (1/2) of the cost of the
third appraiser.

          Within thirty (30) days after the selection of the third appraiser, a
majority of the appraisers shall set the then fair market rental value of the
Premises.  If a majority of the appraisers are unable to set the then fair
market rental value of the Premises within thirty (30) days after selection of
the third appraiser, the three (3) appraisals shall be averaged and the average
shall be the then fair market rental value of the Premises.

     3.   Definitions.  Capitalized terms used in this Rider without definition
          -----------                                                          
shall have the definition assigned to such terms in the Lease to which this
Rider is attached, unless the context requires otherwise.

     4.   Full Force and Effect.  Except as specifically modified by this Rider,
          ---------------------                                                 
the Lease to which this Rider is attached remains in full force and effect.



---------------------------------   --------------------------------- 
Landlord's Initials                 Tenant's Initials


                                   Rider 1-2
<PAGE>
 
                                   RIDER "2"
                                   ---------

     Rider 2 to Lease dated December ____, 1997, between SEOC I LIMITED
     PARTNERSHIP, an Arizona limited partnership ("Landlord"), and CBT SYSTEMS
                                                   --------                   
     USA, LTD., a Delaware corporation ("Tenant").
                                         ------   


     1.   Right of First Refusal to Lease.  Provided that any Event of Default
          -------------------------------                                     
does not exist at the time of exercise, then at such time as Landlord receives a
lease proposal (the "Proposal") from a specific bona fide prospective tenant to
                     --------                                                  
lease all or any portion of the office space in the Project that is currently
leased (or negotiated to be leased) to Safe Ride or Mayo Clinic or any other
space in the Building (the "Refusal Space"), which Proposal Landlord is willing
                            -------------                                      
to accept (except for the portions of Building E which are vacant as of the date
of this Lease, as to the initial leasing of such space, in which case Landlord
will notify Tenant of the Proposal, whether Landlord is willing to accept such
Proposal or not, Landlord shall notify Tenant of the Proposal (the "Proposal
                                                                    --------
Notice") and Tenant shall have an option (the "Option"), exercisable by written
------                                         ------                          
notice to Landlord within ten (10) business days (the (3) business days in case
of Building E space) after receipt of the Proposal Notice to lease all of the
Refusal Space upon the same terms and conditions as are contained in the
Proposal, except that the term shall be continuous with the term of this Lease
and otherwise be substantially the same as the terms and conditions of this
Lease.  Promptly after Tenant exercises the Option, Landlord and Tenant shall
execute a supplemental agreement to this Lease, in a form satisfactory to
Landlord and Tenant, incorporating the Refusal Space as part of the Leased
Premises.  If Tenant does not timely exercise the Option, or if Tenant does not
execute a supplemental agreement to this Lease within thirty (30) days (seven
(7) business days in case of portions of Building E which are vacant, as of the
date of this Lease as to the initial leasing of such space) after notice by
Tenant to Landlord of its election to exercise the Option (and both Landlord and
Tenant agree to use all reasonable efforts to accomplish same), the Option shall
be deemed waived and Landlord may enter into an agreement with the specific bona
fide prospective tenant who submitted the Proposal without liability to Tenant,
provided that such lease is on terms not materially more favorable to such party
than those contained in the Proposal and provided that such lease is consummated
within ninety (90) days after the waiver of the Option.  If Landlord does not
lease the Refusal Space within ninety (90) days after the expiration of said ten
(10) business day period, any further transaction shall be deemed a new
determination by Landlord to lease such space and the provisions of this
paragraph shall again be applicable.  Tenant's right of first refusal shall be
continuous during the entire Term.  Tenant's rejection of any particular offer
shall not relieve Landlord of its obligation to again offer any Refusal Space to
Tenant at any time that the Refusal Space subsequently becomes available.
Landlord represents that the Refusal Space is currently subject only to the
following leases and other rights, and agrees that Landlord shall not grant any
such rights in the Refusal Space except such rights that are expressly subject
to Tenant's right hereunder:  Landlord's lease with Mayo Clinic and Landlord's
lease with Safe Ride Services, Inc.

     2.   Rights Personal to Tenant.  The rights granted to Tenant pursuant to
          -------------------------                                           
this Rider "2" are personal to the originally named Tenant, except for a
Permitted Transfer, and shall automatically terminate upon the assignment of the
Lease or upon a sublease of the entire Leased Premises for the balance of the
Term.

     3.   Definitions.  Capitalized terms used in this Rider without definition
          -----------                                                          
shall have the definition assigned to such terms in the Lease to which this
Rider is attached, unless the context requires otherwise.

     4.   Full Force and Effect.  Except as specifically modified by this Rider,
          ---------------------                                                 
the Lease to which this Rider is attached remains in full force and effect.



 
Landlord's Initials                 Tenant's Initials for CBT Systems USA Ltd



                                   Rider 2-1
<PAGE>
 
                                  EXHIBIT "A"
                                  -----------

                        LEGAL DESCRIPTION OF THE PROJECT
                        --------------------------------



                                      A-1
<PAGE>
 
                                  EXHIBIT "B"
                                  -----------


                                   FLOOR PLAN
                                   ----------



                                      B-1
<PAGE>
 
                                  EXHIBIT "C"
                                  -----------

                        MEMORANDUM OF COMMENCEMENT DATE
                        -------------------------------


     THIS MEMORANDUM OF COMMENCEMENT DATE is entered into this ___ day of
December, 1997 by SEOC I LIMITED PARTNERSHIP, an Arizona limited partnership
("Landlord"), and CBT SYSTEMS USA, LTD., a Delaware corporation ("Tenant").
----------                                                        ------   

                                    RECITALS
                                    --------

     A.   Landlord and Tenant have previously executed that certain Office Lease
dated December ____, 1997 ("Lease"), pursuant to which Tenant has leased from
                            -----                                            
Landlord certain premises more particularly described therein.

     B.   Pursuant to the provisions of Article 34 of the Lease, Landlord and
                                        ----------                           
Tenant have agreed to execute this Memorandum of Commencement Date to specify
the Commencement Date of the Lease Term.

     NOW, THEREFORE, in consideration of the foregoing recitals, the execution
and delivery of the Lease and other good and valuable considerations, the
receipt, sufficiency and validity which is hereby acknowledged, Landlord and
Tenant agree as follows:

     1.   Commencement Date.  The Commencement Date is ______________________,
          -----------------                                                   
and the expiration date of the Lease is ________________________________.

     2.   Definitions.  Capitalized terms used in this Memorandum of
          -----------                                               
Commencement Date without definition shall have the meanings assigned to such
terms in the Lease, unless the context requires otherwise.

     3.   Full Force and Effect.  Except as specifically modified by this
          ---------------------                                          
Memorandum of Commencement Date, the Lease remains in full force and effect.

     IN WITNESS WHEREOF, Landlord and Tenant have executed this Memorandum of
Commencement Date as of the date and year first above written.


TENANT:                                 LANDLORD:
 
CBT SYSTEMS USA, LTD., a Delaware       SEOC I LIMITED PARTNERSHIP, an
corporation                             Arizona limited partnership
 
                                        By: Cavan Investments, Ltd., an
                                            Arizona corporation, its General
By:                                         Partner
   ----------------------------- 
Name:                            
     --------------------------- 
Its:                             
    ---------------------------- 
                                        By:                              
                                           -----------------------------
                                        Name:                           
                                             ---------------------------
                                        Its:                            
                                            ---------------------------- 



                                      C-1
<PAGE>
 
                                  EXHIBIT "D"
                                  -----------

                        RESERVED COVERED PARKING LICENSE
                        --------------------------------


     THIS RESERVED COVERED PARKING LICENSE (this "License") is made as of the
                                                  -------                    
____ day of December, 1997, between SEOC I LIMITED PARTNERSHIP, an Arizona
limited partnership ("Licensor"), and CBT SYSTEMS USA, LTD., a Delaware
                      --------                                         
corporation ("Licensee"), whose address is 1005 Hamilton Court, Menlo Park,
              --------                                                     
California 94025.

     1.   LICENSE.  Licensor hereby grants Licensee a license to use
          -------                                                   
________________ (____) reserved covered parking spaces (the "Spaces") in the
                                                              ------         
parking accommodations (the "Parking Accommodations") of the project (the
                             ----------------------                      
"Project") located at 16100 North Greenway-Hayden Loop, Scottsdale, Arizona
--------                                                                   
85260, as cross-hatched on the site plan attached hereto as Exhibit "A", for a
                                                            -----------       
term the same as the term of the Lease referred to in Paragraph 2 hereof.  Each
                                                      -----------              
Space shall be used solely for the parking of one automobile therein by Licensee
in accordance with the terms of this License.

     2.   THE LEASE.  Anything herein to the contrary notwithstanding, this
          ---------                                                        
License shall terminate no later than the date of termination of the Lease (the
"Lease") between Licensor, as Landlord, and Licensee, as Tenant, for space in
 -----                                                                       
the Project of even date herewith, whether such termination occurs at the end of
the scheduled Lease term or prior thereto.  A breach of this License by Tenant
shall be deemed a breach of the Lease by Tenant and after notice given in
accordance with the terms of the Lease and the failure of Tenant to cure within
fifteen (15) days of such notice, Landlord shall have all remedies available
herein, under the Lease, and at law or in equity.  In the event the term of the
Lease is extended, the term of this License shall also be extended to correspond
with the Lease Term.

     3.   MONTHLY FEE.  Licensee agrees to pay as a monthly fee for this License
          -----------                                                           
Licensor's current fee for each Space licensed, payable on or before the first
day of each month in advance.  The monthly fee which Licensee shall pay is
$25.00 per space.

     4.   DESIGNATION OF SPACES.  This License is for ______________ (____)
          ---------------------                                            
reserved covered parking Spaces in the area of the Parking Accommodations cross-
hatched on Exhibit "B" attached hereto, which area may be redesignated from time
           -----------                                                          
to time by Licensor.  The initial Spaces designated for Licensee are cross-
hatched on Exhibit "B" attached hereto.
           -----------                 

     5.   DESIGNATION OF AUTOMOBILE.  Only vehicles designated by Licensee to
          -------------------------                                          
Licensor may be parked or stored in the Spaces, provided, however, that Licensee
may change its automobile designations at any time upon written notice to
Licensor or for temporary use upon notification given to the garage attendant,
if any.  No more than one (1) automobile per Space licensed hereunder shall be
parked or stored under Licensee's rights hereunder at any one time.

     6.   NO ADDITIONAL SERVICES.  This License is for self-service storage or
          ----------------------                                              
parking only and does not include the rights to any additional services, which
services may be made available by Licensor from time to time at an additional
charge.

     7.   INDEMNITY.  Licensor and its agents and employees shall not be liable
          ---------                                                            
for loss or damage to any vehicle parked or stored by Licensee or under
Licensee's rights herein and/or to the contents thereof caused by fire, theft,
vandalism, collision, explosion, earthquake, storms, natural disasters, strikes,
riots or by any other causes, unless caused by the gross negligence or willful
misconduct of Licensor or its agents, employees or contractors, or Licensor's
breach of this License, and Licensee (a) waives and agrees to hold Licensor
harmless from any claim against Licensor, its agents and employees for and in
respect thereto, and (b) hereby agrees to indemnify and defend Licensor, its
agents and employees against all claims for any damage to any such vehicle or
its contents from any cause whatsoever, unless caused by the gross negligence or
willful misconduct of Licensor, or its agents, employees or contractors, or
Licensor's breach of this License.

     8.   RELATIONSHIP OF PARTIES.  The relationship between Licensor and
          -----------------------                                        
Licensee constitutes a license to use the Parking Accommodations subject to the
terms and conditions of this License only and neither such relationship nor the
storage or parking of any automobile thereunder shall constitute a bailment nor
create the relationship of bailor and bailee.

     9.   NOTICES.  All notices hereunder shall be given in accordance with the
          -------                                                              
terms of the Lease.


                                      D-1
<PAGE>
 
     10.  SUBORDINATION AND ATTORNMENT.  This License shall be subject and
          ----------------------------                                    
subordinate to any mortgage, deed of trust or ground lease now or hereafter
placed on the Project, or any portion thereof, and to replacements, renewals and
extensions thereof, and Licensee, upon request by Licensor, shall execute
instruments (in form satisfactory to Licensor) acknowledging such subordination.

     11.  NO WASTE.  Licensee covenants not to cause any waste or damage or
          --------                                                         
disfigurement or injury to the Project.

     12.  CLOSURE OF FACILITY.  Licensor shall have the right to close any
          -------------------                                             
portion of the Parking Accommodations and deny access thereto in connection with
any repairs or in an emergency, as it may require, without liability, cost or
abatement of fee.

     13.  RULES.  Licensee shall perform, observe and comply with such rules of
          -----                                                                
the Project as may be reasonably adopted by Licensor in respect of the use and
operation of said Parking Accommodations.

     14.  REGULATIONS.  Licensee shall, when using the Parking Accommodations,
          -----------                                                         
observe and obey all signs regarding fire lanes and no parking zones, and when
parking always park between designated lines.  Licensor reserves the right to
tow away, or otherwise impound, at the expense of the owner or operator, any
vehicle which is improperly parked or parked in a no parking zone.  No overnight
parking shall be allowed in the Parking Accommodations.

     IN WITNESS WHEREOF, the parties have executed this agreement as of the day
and year first above written.


LICENSOR:                               LICENSEE:
 
SEOC I LIMITED PARTNERSHIP, an          CBT SYSTEMS USA, LTD., a Delaware
Arizona limited partnership             corporation
 
By:  Cavan Investments, Ltd., an
     Arizona corporation, its General
     Partner
                                        By:                                
                                           ------------------------------- 
                                        Name:                              
                                             ----------------------------- 
                                        Its:                               
                                            ------------------------------ 
     By:                               
        -------------------------------
     Name:                             
          -----------------------------
     Its:                              
         ------------------------------ 

                                      D-2
<PAGE>
 
                                  EXHIBIT "E"
                                  -----------

                                   RESERVED
                                   --------




                                     E-1 
<PAGE>
 
                                  EXHIBIT "F"
                                  -----------

                           UNRESERVED PARKING LICENSE
                           --------------------------


     THIS UNRESERVED PARKING LICENSE (this "License") is made as of the ____ day
                                            -------                             
of December, 1997, between SEOC I LIMITED PARTNERSHIP, an Arizona limited
partnership ("Licensor"), and CBT SYSTEMS USA, LTD., a Delaware corporation
              --------                                                     
("Licensee"), whose address is 1005 Hamilton Court, Menlo Park, California
----------                                                                
94025.

     1.   LICENSE.  Licensor hereby grants Licensee a license to use ___________
          -------                                                               
(____) unreserved uncovered parking spaces (the "Spaces") in the parking
                                                 ------                 
accommodations (the "Parking Accommodations") of the project (the "Project")
                     ----------------------                        -------  
located at 16100 North Greenway-Hayden Loop, Scottsdale, Arizona 85260, as
cross-hatched on the site plan attached hereto as Exhibit "A", for a term the
                                                  -----------                
same as the term of the Lease referred to in Paragraph 2 hereof.  Each Space
                                             -----------                    
shall be used solely for the parking of one automobile therein by Licensee in
accordance with the terms of this License.

     2.   THE LEASE.  Anything herein to the contrary notwithstanding, this
          ---------                                                        
License shall terminate no later than the date of termination of the Lease (the
"Lease") between Licensor, as Landlord, and Licensee, as Tenant, for space in
 -----                                                                       
the Project of even date herewith, whether such termination occurs at the end of
the scheduled Lease term or prior thereto.  A breach of this License by Tenant
shall be deemed a breach of the Lease by Tenant and after notice given in
accordance with the terms of the Lease and the failure of Tenant to cure within
the applicable period under the Lease after such notice, Landlord shall have all
remedies available herein, under the Lease, and at law or in equity.  In the
event the term of the Lease is extended, the term of this License shall also be
extended to correspond with the Lease Term.

     3.   MONTHLY FEE.  No charge.
          -----------             

     4.   DESIGNATION OF SPACES.  This License is for ______________ (____)
          ---------------------                                            
unreserved uncovered parking Spaces in the area of the Parking Accommodations
cross-hatched on Exhibit "B" attached hereto; provided, however, Licensor may
                 -----------                                                 
designate specific Spaces in such location.

     5.   DESIGNATION OF AUTOMOBILE.  Only vehicles designated by Licensee to
          -------------------------                                          
Licensor may be parked or stored in the Spaces, provided, however, that Licensee
may change its automobile designations at any time upon written notice to
Licensor or for temporary use upon notification given to the garage attendant,
if any.  No more than one (1) automobile per Space licensed hereunder shall be
parked or stored under Licensee's rights hereunder at any one time.

     6.   NO ADDITIONAL SERVICES.  This License is for self-service storage or
          ----------------------                                              
parking only and does not include the rights to any additional services, which
services may be made available by Licensor from time to time at an additional
charge.

     7.   INDEMNITY.  Licensor and its agents and employees shall not be liable
          ---------                                                            
for loss or damage to any vehicle parked or stored by Licensee or under
Licensee's rights herein and/or to the contents thereof caused by fire, theft,
vandalism, collision, explosion, earthquake, storms, natural disasters, strikes,
riots or by any other causes, unless caused by the negligence or willful
misconduct of Licensor or its agents, employees or contractors, or Licensor's
breach of this License, and Licensee (a) waives and agrees to hold Licensor
harmless from any claim against Licensor, its agents and employees for and in
respect thereto, and (b) hereby agrees to indemnify and defend Licensor, its
agents and employees against all claims for any damage to any such vehicle or
its contents from any cause whatsoever, unless caused by the negligence or
willful misconduct of Licensor, or its agents, employees or contractors, or
Licensor's breach of this License.

     8.   RELATIONSHIP OF PARTIES.  The relationship between Licensor and
          -----------------------                                        
Licensee constitutes a license to use the Parking Accommodations subject to the
terms and conditions of this License only and neither such relationship nor the
storage or parking of any automobile thereunder shall constitute a bailment nor
create the relationship of bailor and bailee.

     9.   NOTICES.  All notices hereunder shall be given in accordance with the
          -------                                                              
terms of the Lease.

     10.  SUBORDINATION AND ATTORNMENT.  This License shall be subject and
          ----------------------------                                    
subordinate to any mortgage, deed of trust or ground lease now or hereafter
placed on the Project, or any portion thereof, and to replacements, renewals and
extensions thereof, and Licensee, upon request by Licensor, shall execute
instruments (in form satisfactory to Licensor) acknowledging such subordination.

                                      F-1
<PAGE>
 
     11.  NO WASTE.  Licensee covenants not to cause any waste or damage or
          --------                                                         
disfigurement or injury to the Project.

     12.  CLOSURE OF FACILITY.  Licensor shall have the right to close any
          -------------------                                             
portion of the Parking Accommodations and deny access thereto in connection with
any repairs or in an emergency, as it may require, without liability, cost or
abatement of fee.

     13.  RULES.  Licensee shall perform, observe and comply with such rules of
          -----                                                                
the Project as may be reasonably adopted by Licensor in respect of the use and
operation of said Parking Accommodations.

     14.  REGULATIONS.  Licensee shall, when using the Parking Accommodations,
          -----------                                                         
observe and obey all signs regarding fire lanes and no parking zones, and when
parking always park between designated lines.  Licensor reserves the right to
tow away, or otherwise impound, at the expense of the owner or operator, any
vehicle which is improperly parked or parked in a no parking zone.  No overnight
parking shall be allowed in the Parking Accommodations.

     IN WITNESS WHEREOF, the parties have executed this agreement as of the day
and year first above written.


LICENSOR:                               LICENSEE:
 
SEOC I LIMITED PARTNERSHIP, an          CBT SYSTEMS USA, LTD., a Delaware
Arizona limited partnership             corporation
 
By:  Cavan Investments, Ltd., an
     Arizona corporation, its General
     Partner
                                        By:                             
                                           ---------------------------  
                                        Name:                           
                                             -------------------------  
                                        Its:                            
                                            --------------------------  
      
     By:                            
        --------------------------- 
     Name:                          
          ------------------------- 
     Its:                           
         -------------------------- 


                                      F-2
<PAGE>
 
                                  EXHIBIT "G"
                                  -----------

                                  WORK LETTER
                                  -----------


     In order to induce Tenant to enter into the Lease (which is incorporated
herein by reference to the extent that the provisions of this Work Letter may
apply thereto) and in consideration of the mutual covenants hereinafter
contained, Landlord and Tenant agree as follows:

     1.   COMPLETION SCHEDULE.  Attached to this Work Letter is a schedule (the
          -------------------                                                  
"Work Schedule") setting forth the time table for the planning and completion of
 -------------                                                                  
the installation of the tenant improvements to be constructed in the Leased
Premises (the "Tenant Improvements").  The Work Schedule sets forth each of the
               -------------------                                             
various items of work to be done in connection with the completion of the Tenant
Improvements and shall become the basis for completing the Tenant Improvements.
Landlord and Tenant acknowledge and agree that time is of the essence with
respect to their respective obligations as set forth in this Work Letter.

     2.   TENANT IMPROVEMENTS.  The Tenant Improvements shall include the work
          -------------------                                                 
described on Annex I to this Exhibit "G", which work shall be done in the Leased
             -------         -----------                                        
Premises pursuant to the Tenant Improvements Plans described in Paragraph 3
                                                                -----------
below.  Landlord hereby approves of Tenant's construction of the improvements
described in Annex I.
             ------- 

     3.   TENANT IMPROVEMENT PLANS.  Tenant has selected and Landlord has
          ------------------------                                       
approved McCarthy Nordberg as Tenant's architect.  Tenant's architect shall
prepare space plans and final working drawings and specifications for the Tenant
Improvements.  Such final working drawings and specifications are referred to in
this Work Letter as the "Tenant Improvement Plans."  Landlord and Tenant have
                         ------------------------                            
approved Jokake as Landlord's contractor ("Contractor").
                                           ----------   

     4.   PREPARATION OF TENANT IMPROVEMENT PLANS AND FINAL PRICING.  After the
          ---------------------------------------------------------            
preparation of the space plan and after Tenant's approval thereof in accordance
with the Work Schedule, Tenant shall cause its architect to prepare and submit
to Landlord for its reasonable approval the Tenant Improvement Plans.  Promptly
after the approval of the Tenant Improvement Plans by Landlord and Tenant in
accordance with the Work Schedule, the Tenant Improvement Plans shall be
submitted by Landlord to the appropriate governmental body for plan checking and
building permits.  Tenant shall cause to be made such changes in the Tenant
Improvement Plans necessary to obtain required permits.  Tenant acknowledges
that after final approval of the Tenant Improvement Plans, no further changes to
the Tenant Improvement Plans may be made without the prior written consent of
Landlord, which consent shall not be unreasonably withheld but may be
conditioned on the agreement by Tenant to pay all additional costs and expenses
resulting from such requested changes that exceed the Allowance (defined below).

     5.   CONSTRUCTION OF TENANT IMPROVEMENTS.  After the Tenant Improvement
          -----------------------------------                               
Plans have been prepared and approved, and building permits for the Tenant
Improvements have been issued, Landlord shall enter into a construction contract
with its contractor for the installation of the Tenant Improvements in
accordance with the Tenant Improvement Plans.  The Tenant Improvements shall be
constructed in a good, workmanlike and lien free manner, and in conformance with
applicable building codes.  Landlord shall supervise the completion of the
Tenant Improvements at no charge to Tenant.  Landlord shall cause the Tenant
Improvements to be completed in accordance with the Work Schedule.  The cost of
the Tenant Improvements shall be paid as provided in Paragraph 6 below.
                                                     -----------        
Landlord shall cause to be prepared and delivered to Tenant, as quickly as
possible upon Landlord's approval of the Tenant Improvement Plans, an estimate
of the total cost for the Tenant Improvements ("Cost Estimate").  Within ten
                                                -------------               
(10) days after receipt thereof, at its election (i) Tenant may approve the Cost
Estimate, or (ii) Tenant may make changes to the Tenant Improvement Plans that
are necessary, in Tenant's opinion, to reduce costs.  Notwithstanding anything
to the contrary herein, Landlord shall not unreasonably withhold its approval of
the Tenant Improvement Plans or changes to the Tenant Improvement Plans, and
Landlord and Tenant shall confer and negotiate in good faith to reach agreement
upon the Tenant Improvement Plans, modifications to the Tenant Improvement
Plans, and the Cost Estimate as a consequence of such modifications.  The Tenant
Improvement Plans shall be bid by the Contractor to at least three (3) mutually
approved subcontractors, if requested by Tenant.  Landlord and Tenant shall have
the right to receive the bids and Landlord agrees to permit Tenant to assist in
negotiating subcontractor fees and bid costs for labor and materials and to
designate the lowest bidding subcontractor to be selected.  Tenant shall have
the right to reasonably approve the contract between Landlord and Contractor and
to have copies of all contracts between the Contractor and the subcontracts.
The construction agreement between Landlord and Contractor shall provide that
Contractor shall (a) provide and pay for all labor, materials, equipment, tools,
construction equipment and machinery, water, heat and utilities, transportation
and other facilities and services
necessary for proper 

                                      G-1
<PAGE>
 
execution and completion of the Tenant Improvements; (b) supervise and direct
the construction of the Tenant Improvements using contractor's best skills and
attention and be fully responsible for and have control over construction means,
methods, techniques, sequences and procedures for coordinating all portions of
the work under the contract; (c) review, approve and submit to Tenant's
architect shop drawings, product data, samples and submittals required by the
contract documents with promptness and in sequence as to cause no delay in the
construction schedule; (d) take appropriate field measurements and verify field
conditions before commencing construction of Tenant Improvements; and (e) take
reasonable precautions for safety and provide reasonable protection to prevent
damage, injury or loss.

     6.   PAYMENT OF THE COST OF THE TENANT IMPROVEMENTS.
          ---------------------------------------------- 

          a.   TENANT IMPROVEMENT ALLOWANCE.  Landlord hereby grants to Tenant a
               ----------------------------                                     
Tenant Improvement allowance (the "Allowance") based upon a calculation of
Twenty Five and No/100 Dollars ($25.00) per usable square foot of the Leased
Premises.  Landlord and Tenant agree that the usable square footage of the
Leased Premises is twenty five thousand five hundred seventy one (25,571) usable
square feet.  The Allowance shall be used only for:

               (i) Payment of the cost preparing the space plan and the final
working drawings and specifications, including mechanical, electrical and
structural drawings and of all other aspects of the Tenant Improvement Plans,
including the charges of Tenant's space planner and architect, design consultant
and project manager.

               (ii) The payment of permit and license fees relating to
construction of the Tenant Improvements; and

               (iii)  Construction of the Tenant Improvements, including without
limitation the following:

                        (1) Installation within the Leased Premises of all
partitioning, doors, floor coverings, finishes, ceilings, wall coverings and
paintings, millwork and similar items;

                        (2) All electrical wiring, lighting fixtures, outlets
and switches, and other electrical work to be installed within the Leased
Premises;

                        (3) The furnishing and installation of all duct work,
terminal boxes, defusers and accessories required for the completion of the
heating, ventilation and air conditioning systems within the Leased Premises.

                        (4) Any additional Tenant requirements including, but
not limited to odor control, special heating, ventilation and air conditioning,
noise or vibration control or other special systems;

                        (5) All fire and life safety control systems such as
fire walls, sprinklers, halon, fire alarms, including piping, wiring and
accessories installed within the Leased Premises; and

                        (6) All plumbing, fixtures, pipes and accessories to be
installed within the Leased Premises;

                        (7) All monument and directory signage; and

                        (8) All computer, data and voice cabling.

Notwithstanding the foregoing, the cost of the Tenant Improvements shall not
include (and Tenant shall have no responsibility for and the Allowance shall not
be used for) the following:  (a) costs of improvements which are not shown on or
described in the Tenant Improvement Plans unless otherwise approved by Tenant;
(b) costs incurred to remove Hazardous Materials from the Leased Premises or the
surrounding area; (c) attorneys' fees incurred in connection with negotiation of
construction contracts, and attorneys' fees, experts' fees and other costs in
connection with disputes with third parties; (d) interest and other costs of
financing construction costs; (e) costs incurred as a consequence of delay
(except for Tenant Delay and Force Majeure), construction defects or default by
a contractor; (f) costs recoverable by landlord upon account of warranties and
insurance; (g) restoration costs in excess of insurance proceeds as a
consequence of casualties; (h) penalties and late charges attributable to
Landlord's failure to pay construction costs; (i) costs to bring the Leased
Premises into compliance with applicable laws and

                                      G-2
<PAGE>
 
restrictions, including, without limitation, the Americans With Disabilities Act
and environmental laws beyond those required due to the nature of the Tenant
Improvement Plans; (j) wages, labor and overhead for overtime and premium time
unless part of the contract or authorized by Tenant; (k) offsite management or
other general overhead costs incurred by Landlord; (l) construction management,
profit and overhead charges of Landlord; and (m) costs in excess of the approved
Cost Estimate unless such costs are approved or caused by changes requested by
Tenant.

          b.   ADDITIONAL COSTS.  The cost of each of the items set forth in
               ----------------                                             
Paragraph 6(a) above shall be charged against the Allowance.  In the event the
--------------                                                                
cost of installing the Tenant Improvements, as established by the mutually
approved pricing schedule, shall exceed the Allowance, or in the event any of
the Tenant Improvements are not to be paid for from the Allowance, the excess
shall be paid by Tenant within thirty (30) days after the Commencement Date.

          c.   CHANGES TO TENANT IMPROVEMENT PLANS.  In the event that Tenant
               -----------------------------------                           
shall request any changes or substitutions to the Tenant Improvement Plans,
after the Tenant Improvement Plans have been prepared and the final pricing
established by Landlord and Tenant, any additional costs attributable thereto
shall be paid by Tenant to Landlord prior to the commencement of the work
represented by such changes, unless covered under the Allowance.

          d.   UNUSED ALLOWANCE.  Any unused part of the Allowance shall be
               ----------------                                            
credited toward the first payments due from Tenant for the Annual Basic Rent and
Additional Rent.

     7.   EARLY ENTRY.  Landlord shall permit Tenant and Tenant's agents to
          -----------                                                      
enter the Leased Premises prior to the Commencement Date in order that Tenant
may do such work as may be required by Tenant to make the Leased Premises ready
for Tenant's use and occupancy.  If Landlord permits such entry prior to the
Commencement Date, such permission is conditioned upon Tenant and its agents,
contractors, employees and invitees working in harmony and not interfering with
Landlord and its agents, contractors and employees in the installation of the
Tenant Improvements or in the performance of work for other tenants and
occupants of the Building.  If at any time such entry shall cause or threaten to
cause disharmony or interference, Landlord shall have the right to withdraw such
permission upon twenty-four (24) hours notice to Tenant.  Any entry into the
Leased Premises by Tenant prior to the Commencement Date shall be subject to all
of the terms, covenants, conditions and provisions of the Lease, other than with
respect to Tenant's obligation to pay Annual Basic Rent or Additional Rent.
Tenant acknowledges and agrees that Landlord shall not be liable in any way for
any injury, loss or damage which may occur to Tenant, its agents, contractors
and employees or to Tenant's work and installations made in the Leased Premises
or to property placed therein prior to the Commencement Date, all of the same
being at Tenant's sole risk, provided, however, that Landlord shall be liable to
Tenant for the negligence of Landlord, its agents, contractors and employees.

     8.   SUBSTANTIAL COMPLETION.  As soon as the Tenant Improvements are
          ----------------------                                         
Substantially Complete, Landlord shall deliver possession of the Leased Premises
to Tenant.  "Substantial Completion" shall mean the date when (a) the Tenant
             ----------------------                                         
Improvements are completed and available for Tenant's occupancy in broom clean
condition subject only to completion of punch list items, (b) a Certificate of
Occupancy for permanent occupancy or its equivalent has been issued by the City
or other applicable government agency for the Leased Premises for the permitted
use, (c) all Building systems (including, but not limited to, electrical,
plumbing, heat, air conditioning systems and their distribution into the Leased
Premises) are operational to the extent necessary to service the Leased
Premises, (d) Tenant has been provided with the number of parking spaces to
which it is entitled under the parking licenses attached to the Lease as
                                                                        
Exhibits "D" and "F", and (e) Tenant has been provided a nondisturbance
--------------------                                                   
agreement as provided under the Lease.

     9.   TENANT DELAY.  As used in the Lease, a "Tenant Delay" shall mean any
          ------------                            ------------                
delay by Tenant which affects the construction schedule set forth herein,
provided that (a) Tenant shall be allowed to review the Contractor's schedule
and reasonably approve it, (b) such delays are not beyond Tenant's control
(i.e., Force Majeure and Landlord delays), and (c) Tenant is provided three (3)
business days prior written notice that it is in danger of causing delay (in
which event Tenant may elect to incur premium costs to the extent required
and/or available to prevent or minimize a Tenant Delay).  Claims of delay or
otherwise by either party shall be made within seven (7) business days after the
occurrence of the event giving rise to such claims.

     10.  ASSIGNMENT OF WARRANTIES.  Landlord shall assign to Tenant the non-
          ------------------------                                          
exclusive right to enforce any and all warranties which Landlord may receive
from any contractor, supplier or other person or entity involved with
construction of the Tenant Improvements, which assignment shall continue until
the expiration or sooner termination of the Lease or the expiration of the
warranty, whichever occurs first.

                                      G-3
<PAGE>
 
     11.  CONSTRUCTION OF TENANT IMPROVEMENTS.  Notwithstanding anything to the
          -----------------------------------                                  
contrary in the Lease, effective upon delivery of the Leased Premises to Tenant,
Landlord does hereby warrant that, to the best of its knowledge, (a) the
construction of the Tenant Improvements was performed in accordance with all
rules, regulations, codes, statutes, ordinances, and laws of all governmental
and quasi-governmental authorities, in accordance with the Tenant Improvement
Plans, and in a good and workmanlike manner, (b) all material and equipment
installed therein substantially conformed to the Tenant Improvement Plans and
was new and otherwise of good quality, provided, however, if certain materials
specified in the Tenant Improvement Plans are not available, Landlord may
substitute for such materials, materials of equal quality, subject to Tenant's
prior written approval, (c) all building systems are in good working order; (d)
the roof is in good condition; and (e) the Leased Premises are (and will be)
vacant and will after completion of the Tenant Improvements be in the condition
required by this Lease.

     12.  PUNCH LIST PROCEDURE.  Not later than the day prior to the
          --------------------                                      
Commencement Date, Tenant shall prepare a list (the "Punch List") of any
                                                     ----------         
deficiencies or incompleted work regarding any Tenant Improvements.  Provided
that such items are Landlord's responsibility pursuant to the Tenant Improvement
Plans, subject to Force Majeure, Landlord shall correct such deficiencies or
incompleted work within a reasonable period of time, but in no event later than
thirty (30) days after receipt of the Punch List, after which Landlord shall
have no further obligation to alter, change, decorate or improve the Leased
Premises, except as provided in the Lease, whether to adapt the same for the use
for which it is leased or for any other purpose.  The existence of such
deficiencies or incompleted work shall not effect Tenant's obligation to accept
the Leased Premises as otherwise required hereunder.


                                      G-4
<PAGE>
 
                                    ANNEX I
                                    -------
                                      TO
                                      --
                                  EXHIBIT "G"
                                  -----------


                              TENANT IMPROVEMENTS
                              -------------------


                                   ANNEX I-1
<PAGE>
 
                                  EXHIBIT "H"
                                  -----------

                             RULES AND REGULATIONS
                             ---------------------


     1.   Unless otherwise specifically defined herein, all capitalized terms in
these Rules and Regulations shall have the meaning set forth in the Lease to
which these Rules and Regulations are attached.

     2.   The sidewalks, driveways, entrances, passages, courts, elevators,
vestibules, stairways, corridors or halls of the Building and the Project shall
not be obstructed or encumbered or used for any purpose other than ingress and
egress to and from the premises demised to any tenant or occupant.

     3.   No awnings or other projection shall be attached to the outside walls
or windows of the Building.  No curtains, blinds, shades, or screens shall be
attached to or hung in, or used in connection with, any window or door of the
premises demised to any tenant or occupant, without the prior written consent of
Landlord.  All electrical fixtures hung in any premises demised to any tenant or
occupant must be of a type, quality, design, color, size and general appearance
approved by Landlord.

     4.   No tenant shall place objects against glass partitions, doors or
windows which would be in sight from the Building corridors or from the exterior
of the Building and such tenant will promptly remove any such objects when
requested to do so by Landlord.

     5.   The windows and doors that reflect or admit light and air into the
halls, passageways or other public places in the Building shall not be covered
or obstructed, nor shall any bottles, parcels, or other articles be placed on
any window sills.

     6.   No show cases or other articles shall be put in front of or affixed to
any part of the exterior of the Building or the other buildings in the Project,
nor placed in the halls, corridors, walkways, landscaped areas, vestibules or
other public parts of the Building or the Project.

     7.   The water and wash closets and other plumbing fixtures shall not be
used for any purposes other than those for which they were constructed, and no
sweepings, rubbish, rags or other substances shall be thrown therein.

     8.   Other than for the purpose of normal office decorations, no tenant or
occupant shall mark, paint, drill into, or in any way deface any part of the
Project, the Building or the premises demised to such tenant or occupant.  No
boring, cutting or strings of wires shall be permitted, except with the prior
consent of Landlord, and as Landlord may direct.  No tenant or occupant shall
install any resilient tile or similar floor covering in the premises demised to
such tenant or occupant except in a manner approved by Landlord.

     9.   Any carpeting cemented down by a tenant shall be installed with a
releasable adhesive.  In the event of a violation of the foregoing by a tenant,
Landlord may charge the expense incurred in such removal to such tenant.

     10.  No bicycles, vehicles or animals of any kind (except seeing eye dogs)
shall be brought into or kept in or about the premises demised to any tenant.
No cooking shall be done or permitted in the Building by any tenant without the
written approval of Landlord other than the preparation of beverages, microwave
oven use and vending machines.  No tenant shall cause or permit any unusual or
objectionable odors to emanate from the premises demised to such tenant.

     11.  Except as permitted under the Lease, no space in the Building or the
Project shall be used for manufacturing, for the storage of merchandise, or for
the sale of merchandise, goods or property of any kind at auction.

     12.  No tenant shall make, or permit to be made, any unseemly or disturbing
noises or vibrations or disturb or interfere with other tenants or occupants of
the Building, the Project or neighboring buildings or premises whether by the
use of any musical instrument, radio, television set broadcasting equipment or
other audio device, unmusical noise, whistling, singing, or in any other way.
Nothing shall be thrown out of any doors.

     13.  No additional locks or bolts of any kind shall be placed upon any of
the doors, nor shall any 

                                      H-1
<PAGE>
 
changes be made in locks or the mechanism thereof without the prior consent of
Landlord, which shall not be unreasonably withheld. Each tenant must, upon the
termination of its tenancy, return to Landlord all keys of stores, offices and
toilet rooms, either furnished to, or otherwise procured by, such Tenant.

     14.  All removals from the Building, or the carrying in or out of the
Building or from the premised demised to any tenant, of any safes, freight,
furniture or bulky matter of any description must take place at such time and in
such manner as Landlord or its agents may determine, from time to time.
Landlord reserves the right to inspect all freight to be brought into the
Building and to exclude from the Building all freight which violates any of the
Rules and Regulations or the provisions of such tenant's lease.

     15.  No tenant or occupant shall engage or pay any employees in the
Building or the Project, except those actually working for such tenant or
occupant in the Building or the Project, nor advertise for day laborers giving
an address at the Building or the Project.

     16.  No tenant or occupant shall purchase lighting maintenance, cleaning
towels or other like service, from any company or person not reasonably approved
in writing by Landlord.

     17.  Landlord shall have the right to prohibit any advertising by any
tenant or occupant which, in Landlord's reasonable opinion, tends to impair the
reputation of the Building or the Project or its desirability as a building for
offices, and upon notice from Landlord, such tenant or occupant shall refrain
from or discontinue such advertising.

     18.  Each tenant, before closing and leaving the premises demised to such
tenant at any time, shall see that all entrance doors are locked and all
electrical equipment and lighting fixtures are turned off.  Corridor doors, when
not in use, shall be kept closed.

     19.  Each tenant shall, at its expense, provide artificial light in the
premises demised to such tenant for Landlord's agents, contractors and employees
while performing janitorial or other cleaning services and making repairs or
alterations in said premises.

     20.  No premises shall be used, or permitted to be used for lodging or
sleeping, or for any immoral or illegal purposes.

     21.  The requirements of tenants will be attended to only upon application
at the management office of Landlord.  Building employees shall not be required
to perform, and shall not be requested by any tenant or occupant to perform, and
work outside of their regular duties, unless under specific instructions from
the office of Landlord.

     22.  Canvassing, soliciting and peddling in the Building or the Project are
prohibited and each tenant and occupant shall cooperate in seeking their
prevention.

     23.  There shall not be used in the Building, either by any tenant or
occupant or by their agents or contractors, in the delivery or receipt of
merchandise, freight or other matter, any hand trucks or other means of
conveyance except those equipped with rubber tires, rubber side guards and such
other safeguards as Landlord may require.

     24.  If the premises demised to any tenant become infested with vermin,
such tenant, at its sole cost and expense, shall cause its premises to be
exterminated, from time to time, to the satisfaction of Landlord, and shall
employ such exterminators therefor as shall be approved in writing by Landlord.

     25.  No premises shall be used, or permitted to be used, at any time, as a
store for the sale or display of goods, wares or merchandise of any kind, or as
a restaurant, shop, booth, bootblack or other stand, or for the conduct of any
business or occupation which predominantly involves direct patronage of the
general public in the premises demised to such tenant, or for manufacturing or
for other similar purposes.

     26.  No tenant shall clean any window of the Building from the outside.

     27.  No tenant shall move, or permit to be moved, into or out of the
Building or the premises demised to such tenant, any heavy or bulky matter,
without the specific approval of Landlord.  If any such matter requires special
handling, only a qualified person shall be employed to perform such special
handling.  No tenant shall place or permit to be placed, on any part of the
floor or floors of the premises demised to such tenant, a load exceeding the
floor load per square foot which such floor was designed to 


                                      H-2
<PAGE>
 
carry and which is allowed by law.  Landlord reserves the right to prescribe
the weight and position of safes and other heavy objects, which must be placed
so as to distribute the weight.

     28.  With respect to work being performed by a tenant in its premises with
the approval of Landlord, the tenant shall refer all contractors, contractors'
representatives and installation technicians to Landlord for its supervision,
approval and control prior to the performance of any work or services.  This
provision shall apply to all work performed in the Building and the Project
including installation of telephones, telegraph equipment, electrical devices
and attachments, and installations of every nature affecting floors, walls,
woodwork, trim, ceilings, equipment and any other physical portion of the
Building and the Project.  Such supervision shall be without charge to Tenant.

     29.  Landlord shall not be responsible for lost or stolen personal
property, equipment, money, or jewelry from the premises of tenants or public
rooms whether or not such loss occurs when the Building or the premises are
locked against entry.

     30.  Landlord may permit entrance to the premises of tenants by use of pass
keys controlled by Landlord employees, contractors, or service personnel
directly supervised by Landlord and employees of the United States Postal
Service.

     31.  Each tenant and all of tenant's representatives, shall observe and
comply with the directional and parking signs on the property surrounding the
Building, and Landlord shall not be responsible for any damage to any vehicle
towed because of non-compliance with parking regulations.

     32.  No tenant shall install any radio, telephone, television, microwave or
satellite antenna, loudspeaker, music system or other device on the roof or
exterior walls of the Building or on common walls with adjacent tenants or in
the Project Common Areas.

     33.  Each tenant shall store all trash and garbage within its premises.  No
material shall be placed in the trash boxes or receptacles in the Building or
the Project unless such material may be disposed of in the ordinary and
customary manner of removing and disposing of trash and garbage and will not
result in a violation of any law or ordinance governing such disposal.  All
garbage and refuse disposal shall be made only through entryways and elevators
provided for such purposes and at such times as Landlord shall designate.

     34.  Each tenant shall give prompt notice to landlord of any accidents to
or defects of which Tenant has actual notice in plumbing, electrical or heating
apparatus so that same may be attended to properly.

     35.  Landlord reserves the right to restrict access to and from the
Building between the hours of 6:00 P.M. and 7:00 A.M. on business days, 12:00
P.M. to 8:00 A.M. on Saturdays, and at all hours on Sundays and holidays.
Notwithstanding the foregoing, Tenant and its employees shall have access to the
Premises 24 hours per day all year.

     36.  All tenant and Tenants; servants, employees, agents, visitors,
invitees and licensees shall observe faithfully and comply strictly with the
foregoing Rules and Regulations and such other and further appropriate Rules and
Regulations as Landlord or Landlord's agent from time to time adopt.

     37.  Landlord shall furnish each tenant, at Landlord's expense, with
________ (____) keys to unlock the entry level doors and _________ (____) keys
to unlock each corridor door entry to  each tenant's premises and, at such
tenant's expense, with such additional keys as such tenant may request.  No
tenant shall install or permit to be installed any additional lock on any door
into or inside of the premises demised to that tenant or make or permit to be
made any duplicate of keys to the entry level doors or the doors to such
premises.  Landlord shall be entitled at all times to possession of a duplicate
of all keys to all doors into or inside of the premises demised to tenants of
the Building.  All keys shall remain the property of Landlord.  Upon the
expiration of the Lease Term, each tenant shall surrender all such keys to
Landlord and shall deliver to Landlord the combination to all locks on all
safes, cabinets and vaults which will remain in the premises demised to that
tenant.  Landlord shall be entitled to install, operate and maintain security
systems in or about the Project which monitor, by computer, close circuit
television or otherwise, persons entering or leaving the Project, the Building.
For the purposes of this rule the term "keys" shall mean traditional metallic
                                        ----                                 
keys, plastic or other key cards and other lock opening devices.

     38.  Each person using the Parking Accommodations or other areas designated
by Landlord where parking will be permitted shall comply with all Rules and
Regulations adopted by Landlord with 


                                      H-3
<PAGE>
 
respect to the Parking Accommodations or other areas, including any employee or
visitor parking restrictions, and any sticker or other identification system
established by Landlord. Landlord may refuse to permit any person who violates
any parking rule or regulation to park in the Parking Accommodations or other
areas, and may remove any vehicle which is parked in the Parking Accommodations
or other areas in violation of the parking Rules and Regulations. The Rules and
Regulations applicable to the Parking Accommodations and the outside parking
areas are as follows:

          (a)  The maximum speed limit within the Parking Accommodations shall
               be 5 miles per hour, the maximum speed limit in other parking
               areas shall be 15 miles per hour.

          (b)  All directional signs and arrows must be strictly observed.

          (c)  All vehicles must be parked entirely within painted stall lines.

          (d)  No vehicle may be parked (i) in an area not striped for parking,
               (ii) in a space which has been reserved for visitors or for
               another person or firm, (iii) in an aisle or on a ramp, (iv)
               where a "no parking" sign is posted or which has otherwise
               designated as a no parking area, (v) in a cross hatched area,
               (vi) in an area bearing a "handicapped parking only" or similar
               designation unless the vehicle bears an appropriate handicapped
               designation, (vii) in an area bearing a "loading zone" or similar
               designation unless the vehicle is then engaged in a loading or
               unloading function and (viii) in an area with a posted height
               limitation if the vehicle exceeds the limitation.

          (e)  Parking passes, stickers or other identification devices that may
               be supplied by Landlord shall remain the property of Landlord and
               shall not be transferable.  A replacement charge determined by
               Landlord will be payable by each tenant for loss of any magnetic
               parking card or parking pass or sticker.

          (f)  Garage managers or attendants shall not be authorized to make or
               allow any exceptions to these Rules and Regulations.

          (g)  Each operator shall be required to park and lock his or her own
               vehicle, shall use the Parking Facilities at his or her own risk
               and shall bear full responsibility for all damage to or loss of
               his or her vehicle, and for all injury to persons and damage to
               property caused by his or her operation of the vehicle.

          (h)  Landlord reserves the right to tow away, at the expense of the
               owner, any vehicle which is inappropriately parked or parked in
               violation of these Rules and Regulations.

     39.  Landlord reserves the right at any time and from time to time to
rescind, alter or waive, in whole or in part, any of the Building Rules and
Regulations when it is deemed necessary, desirable or proper, in Landlord's
judgment for its best interest or of the best of the tenants of the Project.  In
the event of a contradiction between the Lease and these Rules and Regulations,
the terms of the Lease shall govern.

     40.  No smoking is permitted within the premises or in the Building
pursuant to Scottsdale Revised Code, (S) 19-16, Smoking Pollution Control
Ordinance.

     Tenant hereby acknowledges receipt of the Building Rules and Regulations.

                              TENANT:

                              CBT SYSTEMS USA, LTD., a Delaware corporation



                              By:
                                 ----------------------------------
                              Name:
                                   --------------------------------
                              Its:
                                  ---------------------------------
                              Date:
                                   --------------------------------


                                      H-4
<PAGE>
 
                                  EXHIBIT "I"
                                  -----------

                             LOADING ZONE SITE PLAN
                             ----------------------




                                      I-1