<PAGE>
                                                                   Exhibit 10.56

                                      LEASE

                                   SEARS TOWER

                             233 SOUTH WACKER DRIVE

                                CHICAGO, ILLINOIS

                                   SPSS, INC.

<PAGE>

                                      LEASE

                                   SEARS TOWER

                             233 SOUTH WACKER DRIVE

                                CHICAGO, ILLINOIS

                                   SPSS, INC.

                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                            PAGE
                                                                            ----
<S>                                                                         <C>
SCHEDULE.................................................................     1

TERMS AND CONDITIONS.....................................................     5

1.    TERM...............................................................     5
2.    BASE RENT..........................................................     5
3.    ADDITIONAL RENT....................................................     5
4.    USE OF THE PREMISES................................................    10
5.    POSSESSION.........................................................    10
6.    SERVICES...........................................................    10
7.    REPAIRS............................................................    15
8.    ADDITIONS AND ALTERATIONS..........................................    16
9.    COVENANT AGAINST LIENS.............................................    17
10.   INSURANCE..........................................................    17
11.   FIRE OR CASUALTY...................................................    19
12.   WAIVER OF CLAIMS - INDEMNIFICATION.................................    20
13.   NONWAIVER..........................................................    21
14.   CONDEMNATION.......................................................    21
15.   ASSIGNMENT AND SUBLETTING..........................................    22
16.   SURRENDER OF POSSESSION............................................    25
17.   HOLDING OVER.......................................................    26
18.   ESTOPPEL CERTIFICATE...............................................    27
19.   OBLIGATIONS TO MORTGAGEES..........................................    27
20.   CERTAIN RIGHTS RESERVED BY LANDLORD................................    28
21.   RULES AND REGULATIONS..............................................    30
22.   DEFAULT AND LANDLORD'S REMEDIES....................................    30
23.   EXPENSES OF ENFORCEMENT............................................    32
24.   COVENANT OF QUIET ENJOYMENT........................................    33
25.   REAL ESTATE BROKER.................................................    33
26.   MISCELLANEOUS......................................................    33
27.   NOTICES............................................................    36
28.   LIMITATION OF LIABILITY............................................    36
29.   RIGHT OF FIRST OFFER...............................................    36
30.   TENANT'S OPTION TO RENEW...........................................    37
31.   SPECIAL IMPROVEMENTS...............................................    37
</TABLE>


                                        i

<PAGE>

                                    EXHIBITS

EXHIBIT A   FLOOR PLAN OF PREMISES

EXHIBIT B   TENANT/CONTRACTOR AND VENDOR GUIDELINES

EXHIBIT C   RULES AND REGULATIONS

EXHIBIT D   ESTOPPEL CERTIFICATE

EXHIBIT E   CONDENSER WATER ADDENDUM


                                       ii

<PAGE>

                                      LEASE
                                   SEARS TOWER
                             233 SOUTH WACKER DRIVE
                                CHICAGO, ILLINOIS

     THIS AGREEMENT OF LEASE made as of this 22nd day of November, 2005
(hereinafter referred to as the "Lease") between 233 S WACKER LLC, a Delaware
limited liability company (hereinafter referred to as "Landlord"), and SPSS,
INC., a Delaware corporation (hereinafter referred to as "Tenant");

                                    SCHEDULE

1.   DESCRIPTION OF PREMISES: The premises designated on the plan attached
     hereto as Exhibit A and containing approximately a total of 41,577 square
     feet of "Rentable Area" on the 9th and 10th floors (being approximately
     25,098 square feet of Rentable Area on the 9th floor and 16,479 square feet
     of Rentable Area on the 10th floor; collectively, the "Premises") in the
     building commonly known as the Sears Tower (the "Building") located at 233
     South Wacker Drive in the City of Chicago, Cook County, Illinois
     (hereinafter referred to together with all present and future easements,
     additions, improvements and other rights appurtenant thereto, as the
     "Land").

2.   USE OF PREMISES: Tenant shall use the Premises solely as general offices
     and customer training and for no other purpose whatsoever.

3.   BASE RENT: The per annum rate of Base Rent and the monthly installments
     thereof are set forth on Schedule 1 attached hereto.

4.   TENANT'S PROPORTIONATE SHARE: shall mean (a) 1.18% for the purposes of
     determining Taxes (as hereinafter defined) payable by Tenant hereunder,
     such percentage being the percentage calculated by dividing the Rentable
     Area contained in the Premises, as determined by Landlord and shown in Item
     1 of this Schedule by 3,530,477 rentable square feet (being ninety-five
     percent (95%) of the aggregate amount of all office and retail space in the
     Building), and (b) 1.27% for purposes of determining Operating Expenses (as
     hereafter defined) payable by Tenant hereunder, such percentage being the
     percentage calculated by dividing the Rentable Area of the Premises, by
     3,284,958 rentable square feet (being ninety-five percent (95%) of the
     aggregate amount of all office space in the Building). Tenant's
     Proportionate Share shall be adjusted proportionately if the number of
     square feet of Rentable Area in the Premises is increased pursuant to
     Section 29 hereof.

5.   COMMENCEMENT DATE: July 1, 2006.

6.   TERMINATION DATE: May 31, 2012.

<PAGE>

7.   ADDRESSES FOR NOTICES:

     IF TO LANDLORD:

          233 S Wacker LLC
          c/o The Chetrit Group
          404 Fifth Avenue, 4th Floor
          New York, New York 10018

          and:

          233 S Wacker LLC
          c/o American Landmark Properties, Ltd.
          8114 Lawndale Avenue
          Skokie, Illinois 60076

          with copies to:

          233 S Wacker LLC
          c/o CB Richard Ellis
          233 South Wacker Drive, Suite 3530
          Chicago, Illinois 60606
          Attention: General Manager

     IF TO TENANT:

          SPSS, Inc.
          233 South Wacker Drive, Suite 950
          Chicago, Illinois 60606
          Attention: Terry Schohn

8.   BROKER: CB Richard Ellis.


                                        2

<PAGE>

     This Lease is subject to the Terms and Conditions and the provisions of any
exhibits attached hereto, which Terms and Conditions and exhibits are hereby
made a part of this Lease.

LANDLORD:                               TENANT:

233 S WACKER LLC,                       SPSS, INC.,
A DELAWARE LIMITED LIABILITY COMPANY    A DELAWARE CORPORATION


By: /s/ John M. Houston                 By: /s/ Raymond H. Panza
    ---------------------------------       ------------------------------------
Its: Authorized Member                  Its: Executive Vice President, Corporate
                                        Operations and Chief Financial Officer


                                        3

<PAGE>

                                   SCHEDULE 1

                                    Base Rent

<TABLE>
<CAPTION>
                                          Annual
                                      Per Square Foot     Monthly       Annual
Period                               Base Rental Rate    Base Rent    Base Rent
------                               ----------------   ----------   -----------
<S>                                  <C>                <C>          <C>
July 1, 2006 - June 30, 2007 .....        $19.00*       $65,830.25   $789,963.00

July 1, 2007 - June 30, 2008 .....        $19.50        $67,562.63   $810,751.50

July 1, 2008 - June 30, 2009 .....        $20.00        $69,295.00   $831,540.00

July 1, 2009 - June 30, 2010 .....        $20.50        $71,027.38   $852,328.50

July 1, 2010 - June 30, 2011 .....        $21.00        $72,759.75   $873,117.00

July 1, 2011 - May 31, 2012 ......        $21.50        $74,492.13   $893,905.50
</TABLE>

*    If Tenant is not in Default under the Lease on the date any such
     installment is due, each of the first four (4) monthly installments of Base
     Rent due under the Lease shall be abated in full and shall not be payable
     by Tenant, subject to the terms of Section 22 of the Lease.


                                        4

<PAGE>

                              TERMS AND CONDITIONS

     Landlord hereby leases to Tenant, and Tenant hereby leases from Landlord,
the premises (hereinafter referred to as the "Premises") described in the
Schedule appearing at the beginning of this Lease (hereinafter referred to as
the "Schedule") and designated on the plan attached hereto as Exhibit A, subject
to the covenants, terms, provisions and conditions of this Lease.

1.   TERM

     The term of this Lease (hereinafter referred to as the "Term") shall
     commence on the Commencement Date and shall end on the Termination Date
     each as provided in the Schedule, unless sooner terminated as provided
     herein.

2.   BASE RENT

     Tenant shall pay to Landlord at P.O. Box 8000, Department 794, Buffalo, New
     York 14267, or at such other place as Landlord or Landlord's agent may from
     time to time designate in writing, in currency which, at the time of
     payment, is legal tender for private or public debts in the United States
     of America, the applicable annual Base Rent set forth in Schedule 1 payable
     in equal monthly installments in the applicable amounts set forth in
     Schedule 1 in advance on or before the first day of each and every month
     during the Term without demand and without any abatement, setoff or
     deduction whatsoever, except as specifically set forth in this Lease. Such
     Base Rent shall be escalated on each anniversary of the Commencement Date
     as set forth in Schedule 1. Each period of twelve (12) months beginning on
     the Commencement Date or on any anniversary thereof and ending on the day
     before the following anniversary of the Commencement Date or on the
     Termination Date, as the case may be, is hereinafter referred to as a
     "Lease Year." Any Base Rent payable for a partial month at the beginning of
     the Term shall be paid on the first day of the first full calendar month of
     the Term. Any Base Rent payable for a partial month at the end of the Term
     shall be paid on the first day of such month.

3.   ADDITIONAL RENT

     In addition to paying the Base Rent specified in Section 2 hereof, Tenant
     shall pay as "Additional Rent" the amounts described in this Section 3.
     Such Additional Rent paid by Tenant and other tenants in the Building shall
     reimburse Landlord for all expenses of owning, operating and maintaining
     the Land and the Building, except as expressly excluded below, and shall
     permit Landlord to receive the Base Rent as "net" rent. The Base Rent and
     the Additional Rent and all other amounts due under this Lease are herein
     collectively referred to as the "Rent." All Additional Rent shall be
     payable for the same periods and in the same manner, time and place as the
     Base Rent is to be paid. Without limitation on other obligations of Tenant
     which shall survive the expiration of the Term, the obligations of Tenant
     to pay Additional Rent shall survive the expiration of the Term. For any
     Calendar Year which is not wholly included in the Term, Tenant shall be
     obligated to pay only a pro rata share of the Additional Rent for such
     Calendar Year, based on the number of days of the Term falling within such
     Calendar Year. Except as specifically provided in this Lease, Rent shall be
     paid without abatement, deduction or set off of any kind, it being the
     intention of the parties that, to the full extent permitted by


                                       5

<PAGE>

     law, Tenant's covenant to pay Rent shall be independent of all other
     covenants contained in this Lease.

     (a)  CERTAIN DEFINITIONS. As used in this Lease, the terms:

          (i)  "Base Year" shall mean Calendar Year 2006.

          (ii) "Calendar Year" shall mean each calendar year in which any part
               of the Term falls, through and including the year in which the
               Term expires.

          (iii) "Operating Expenses" shall mean all expenses, costs and
               disbursements of every kind and nature (determined for the
               applicable Calendar Year on an accrual basis) paid or incurred by
               Landlord or its managing agent in connection with the ownership,
               management, operation, maintenance and repair of the Land and
               Building (including, without limitation, the cost of providing
               electricity for lighting the Premises as provided in Subsection
               6(a)(ii) below and other office space), except the following:

               A.   Taxes (as hereinafter defined);

               B.   Costs of capital improvements to any tenant's premises;

               C.   Principal or interest payments on loans secured by mortgages
                    or trust deeds on the Building or Land or rent payable on
                    any ground lease of the Land;

               D.   Costs of capital improvements to the Building, except that
                    Operating Expenses shall include (1) the costs of any
                    capital improvement completed during the Term which is
                    intended to reduce any component of Operating Expenses and
                    (2) the costs of any capital improvement which is made by
                    Landlord to keep the Land or Building in compliance with all
                    governmental rules and regulations applicable from time to
                    time thereto, in each case as evenly amortized over the
                    useful life of each such capital improvement with interest
                    on the unamortized amount at the greater of (A) ten percent
                    (10%) per annum or (B) two percent (2%) per annum above the
                    "prime rate" or "corporate base rate" announced from time to
                    time by a major Chicago bank selected by Landlord (the
                    "Prime Rate") (but in no event at a rate which is more than
                    the highest lawful rate allowable in the State of Illinois);

               E.   Costs of utilities and other services provided to and used
                    in the operation of the retail stores in the Building,
                    including tourist retail stores, provided that the costs of
                    operating and maintaining the common areas adjoining such
                    retail stores shall be included in Operating Expenses; and


                                       6

<PAGE>

               F.   Costs and expenses incurred in connection with leasing space
                    in the Building, such as leasing commissions and advertising
                    and promotional expenses;

               G.   Costs incurred in connection with the parking garage;

               H.   Any costs paid to Landlord's management agent which are in
                    excess of customary market amounts for other Class A office
                    buildings in downtown Chicago;

               I.   Costs of repairs, alterations or replacements caused by
                    casualty losses or other events to the extent Landlord
                    receives insurance reimbursement;

               J.   All material costs, interests and fines arising by reason of
                    the violation by Landlord of any legal requirement
                    applicable to the Building.

          (iv) "Taxes" shall mean taxes levied, assessed, imposed or accruing
               during the Term (or which Landlord is obligated to pay on behalf
               of any other person or entity having any interest in the Land or
               the Building) in connection with the Land, the Building, the
               operation thereof or any rights or responsibilities related
               thereto. "Taxes" shall include without limitation: (a) real
               estate taxes and assessments, special or otherwise, levied,
               assessed, imposed or accruing during the Term upon the Land or
               Building; (b) any tax, assessment, charge or fee which is imposed
               in substitution for, or in lieu of an increase in, such real
               estate taxes; (c) a tax on gross rents or leases or any income or
               franchise tax based on Landlord's income from the Land and
               Building which taxes such income in a different manner than
               income from sources other than the ownership and operation of
               income-producing real estate, which is substantively the
               functional equivalent of a tax on gross rents or leases, but is
               called by another name; or (d) a tax on the development of real
               estate or the construction or improvement of buildings or
               premises therein. Taxes shall also include, in the year paid, all
               fees for consultants and attorneys and all other costs incurred
               by Landlord in seeking to obtain a reduction of, or a limit on
               the increase in, any Taxes, regardless of whether any reduction
               or limitation is obtained. Taxes shall not include any
               inheritance, estate, succession, transfer, gift, franchise, or
               capital stock tax or any current state or federal income taxes or
               any income taxes other than those described above. With respect
               to any Taxes which include assessments against income or property
               not related to the Land or Building, Taxes shall include only
               that portion of such Taxes which would be payable if the Land and
               Building and all rights related thereto were the only assets of
               Landlord. Taxes shall not include interest or penalties arising
               as a result of a late payment, except to the extent such late
               payment is due to the default of Tenant hereunder.


                                       7

<PAGE>

     (b)  EXPENSE ADJUSTMENT. Tenant shall pay to Landlord or Landlord's agent
          as Additional Rent, an amount ("Expense Adjustment Amount") equal to
          Tenant's Proportionate Share of the amount of Operating Expenses plus
          Tenant's pro rata share of the special allocation of Variable
          Operating Expenses (as defined in Section 3(c)) in excess of Operating
          Expenses and Variable Operating Expenses for the Base Year incurred
          with respect to each Calendar Year or any portion thereof. The Expense
          Adjustment Amount with respect to each Calendar Year shall be paid in
          monthly installments during that Calendar Year in an amount reasonably
          estimated from time to time by Landlord and communicated by written
          notice to Tenant. Landlord shall cause to be kept books and records
          showing Operating Expenses in accordance with an appropriate system of
          accounts and accounting practices consistently maintained. Following
          the close of each Calendar Year, Landlord shall compute the Expense
          Adjustment Amount for that Calendar Year based on the Operating
          Expenses (and any special allocation of Variable Operating Expenses)
          for that Calendar Year and shall deliver to Tenant a statement of the
          Expense Adjustment Amount plus a statement of all estimated
          installments paid by Tenant with respect to that Calendar Year. Tenant
          shall pay to Landlord any deficiency shown by such statement within
          thirty (30) days after Tenant receives the statement. If the
          installments paid exceed the amounts due, Landlord shall either credit
          the excess against payments next due to Landlord from Tenant hereunder
          or at Landlord's option, and if Tenant is not then in default
          hereunder, refund the excess to Tenant no later than thirty (30) days
          thereafter. The foregoing obligations of Landlord and Tenant shall
          survive the expiration of the Term. Delay in computation of the
          Expense Adjustment Amount shall not be deemed a default hereunder or a
          waiver of Landlord's right to collect the Expense Adjustment Amount;
          provided, however, that Landlord shall compute such Expense Adjustment
          Amount not later than twelve (12) months following the close of such
          Calendar Year. Each annual statement of Operating Expenses shall
          itemize Operating Expenses in a reasonably detailed manner and shall
          separately state, and show the basis for calculation of, the amount of
          any amortization of capital expenditures included in Operating
          Expenses as provided above and any allocation of Variable Operating
          Expense as provided below. Tenant shall have the right to cause to be
          audited, by a firm of independent public accountants (not paid on a
          contingency basis) designated by Tenant and satisfactory to Landlord,
          Landlord's records in respect of Operating Expenses, the cost of which
          shall be borne by Tenant unless it is demonstrated that Landlord has
          overstated Tenant's Expense Adjustment Amount by more than 3%, in
          which case Landlord shall bear the cost of such audit. The results of
          such audit shall be deemed final and conclusive as to Landlord and
          Tenant and any amounts due from Landlord or Tenant to the other as
          indicated by the written report of such audit shall be paid within
          thirty (30) days after the receipt by Landlord and Tenant of such
          report. Unless such an audit is commenced within 90 days after
          Tenant's receipt of the statement for a Calendar Year, such statement
          shall be deemed final and conclusive as to Tenant. Tenant's right to
          audit shall not reduce or defer Tenant's obligation to pay the amounts
          shown on any such statement when due, subject to readjustment as
          described above. All information obtained by Tenant in connection with
          such audit shall be utilized by Tenant on a confidential basis and
          shall not be shared with other tenants in the Building.


                                       8

<PAGE>

     (c)  ALLOCATION OF VARIABLE OPERATING EXPENSES. If at any time during the
          Term less than ninety-five percent (95%) of the then current office
          space in the Building is occupied, at Landlord's option those
          components of Operating Expenses which vary with occupancy ("Variable
          Operating Expenses") shall be removed from general Operating Expenses
          and allocated to the portion of the office space in the Building which
          is actually occupied and generating such components of Operating
          Expenses. This special allocation shall be made on a pro rata basis
          over the occupied office space in the Building, based on both the
          comparative Rentable Areas of the Building which are occupied and the
          portion of the Calendar Year during which the portions of the Building
          were occupied. For purposes of this Section, Variable Operating
          Expenses shall mean janitorial services, electricity for overhead
          lighting, HVAC costs and elevator maintenance costs. Operating
          Expenses which do not vary with occupancy, such as public liability
          insurance and lobby maintenance will continue to be allocated on a pro
          rata basis over the office space in the Building whether or not
          occupied and Tenant shall only be responsible for Tenant's
          Proportionate Share of those Operating Expenses.

     (d)  TAX ADJUSTMENT. Tenant shall pay to Landlord or Landlord's agent as
          Additional Rent, an amount ("Tax Adjustment Amount") equal to Tenant's
          Proportionate Share of the amount of Taxes in excess of Taxes for the
          Base Year incurred with respect to each Calendar Year or any portion
          thereof. The Tax Adjustment Amount with respect to each Calendar Year
          shall be paid in monthly installments during that Calendar Year in an
          amount reasonably estimated from time to time by Landlord and
          communicated by written notice to Tenant. If Taxes for any Calendar
          Year are payable in whole or in part before the end of that Calendar
          Year, Tenant shall, within thirty (30) days after the written request
          of Landlord, promptly pay Tenant's Proportionate Share of the payment
          as a special installment, after deducting installments previously paid
          by Tenant under this Section 3(d) for such Calendar Year. Following
          the final payment of Taxes for each Calendar Year, Landlord shall
          compute the Tax Adjustment Amount for that Calendar Year and deliver
          to Tenant a statement of the Tax Adjustment Amount plus a statement of
          all estimated installments paid by Tenant for that Calendar Year.
          Tenant shall pay to Landlord any deficiency shown by the statement
          within thirty (30) days after Tenant receives the statement. If the
          installments paid exceed the actual amount due, Landlord shall either
          credit the excess against payments next due to Landlord from Tenant
          hereunder or at Landlord's option, and if Tenant is not then in
          default hereunder, refund the excess to Tenant no later than thirty
          (30) days thereafter. The amount of any refund of Taxes received by
          Landlord shall be credited against Taxes for the year in which such
          refund is received. The foregoing obligations of Landlord and Tenant
          shall survive the expiration of the Term. In determining the amount of
          Taxes for any Calendar Year, the amount of special assessments to be
          included shall be limited to the amount of the installment (plus any
          interest payable thereon) of the special assessment required to be
          paid during that year as if Landlord had elected to have the special
          assessment paid over the maximum period of time permitted by law. All
          references to Taxes "for" a particular year shall be deemed to refer
          to Taxes levied or assessed for the year without regard to when such
          Taxes are paid or


                                       9

<PAGE>

          payable. Delay in computing the Tax Adjustment Amount shall not be
          deemed a Default hereunder or a waiver of Landlord's right to collect
          the Tax Adjustment Amount; provided that Landlord shall provide a
          final statement of Taxes for a Calendar Year no later than twelve (12)
          months after the due date of the final installment of Taxes for such
          Calendar Year.

4.   USE OF THE PREMISES

     (a)  RESERVED AREAS. This Lease does not give Tenant any right to use, and
          Landlord hereby excludes and reserves for its sole and exclusive use,
          subject to Tenant's express rights hereunder, the following areas in
          and about the Premises: janitor closets, stairways and stairwells,
          fan, mechanical, electrical, telephone and similar rooms (other than
          those installed for Tenant's exclusive use); elevator, pipe and other
          vertical shafts, flues and ducts; all areas above the acoustical
          ceiling (except that Tenant may use the areas above the acoustical
          ceiling for conduit, provided such conduit is encased, meets all codes
          and is otherwise reasonably approved by Landlord and Landlord's
          architect) and below the finished floor covering installed in the
          Premises; all other structural or mechanical elements serving other
          areas of the Building; and all subterranean, mineral, air, light and
          view rights.

     (b)  PERMITTED USE. Tenant shall use and occupy the Premises solely for the
          purposes set forth in the Schedule and for no other purpose.

     (c)  COMPLIANCE WITH LAWS. Tenant shall not use or permit the use of any
          part of the Premises for any purpose prohibited by law. Tenant shall,
          at its sole expense, comply with and conform to all of the
          requirements of all governmental authorities having jurisdiction over
          the Building which relate in any way to the condition, use and
          occupancy of the Premises throughout the entire Term of this Lease.
          Nothing in this Section 4(c) shall be construed to require Tenant to
          modify the Building structure or systems except if the need for such
          modifications is caused by Tenant's use of the Premises other than for
          general office use.

5.   POSSESSION

     (a)  POSSESSION OF THE PREMISES. Tenant is in occupancy of the Premises.
          Tenant acknowledges and agrees that the Premises are in good order and
          satisfactory condition.

6.   SERVICES

     (a)  LIST OF SERVICES. So long as Tenant is not in Default under any
          covenant or condition of this Lease, Landlord shall provide the
          following services on all days during the Term, except Saturdays,
          Sundays and Holidays (herein defined to be New Year's Day, Memorial
          Day, Fourth of July, Labor Day, Thanksgiving Day. and Christmas Day),
          unless otherwise stated:

          (i)  Heating and air conditioning in the Premises from Monday through
               Friday, from 8 a.m. to 6 p.m. and on any Saturday which is not a
               Holiday from 8 a.m. to 1 p.m. Landlord will operate the system of
               distribution


                                       10

<PAGE>

               ducts, supply registers and diffusers, return grilles and
               associated fixtures to provide in the Premises as currently
               partitioned, heating and air conditioning with capacity to
               provide the following results during the business hours set forth
               above; which heating and air conditioning shall, within
               tolerances normal in first class office buildings in downtown
               Chicago, be capable of providing the following: (a) air
               conditioning which shall be capable of maintaining inside space
               conditions of seventy-eight degrees (78 Degrees) Fahrenheit dry
               bulb and fifty percent (50%) relative humidity when outside
               conditions are ninety-two degrees (92 Degrees) Fahrenheit dry
               bulb and seventy-five degrees (75 Degrees) Fahrenheit wet bulb
               and (b) heating which shall be capable of maintaining inside
               space conditions of not less than seventy-two degrees
               (72 Degrees) Fahrenheit when outside air temperatures are not
               less than minus ten degrees (-10 Degrees) Fahrenheit and not more
               than sixty-five degrees (65 Degrees) Fahrenheit. The foregoing is
               based upon occupancy density of not more than one (1) person per
               hundred (100) square feet of floor area, and a maximum electric
               lighting and office machine load of five (5) watts per square
               foot of floor area.

               Tenant will pay for all heating and air conditioning requested
               and furnished prior to or following such hours at rates to be
               established from time to time by Landlord. Landlord's obligations
               with respect to heating and air conditioning are subject to all
               governmental rules, regulations and guidelines applicable
               thereto. The current rate for after hours HVAC is $109 per hour
               per floor. Such rate is subject to change from time to time.
               Wherever heat generating machines or equipment are used by Tenant
               in the Premises, which affect the temperature otherwise
               maintained by the air-cooling system, or where the configuration
               and placement of such equipment creates a per square foot heat
               load above what would be considered normal for office use,
               Landlord reserves the right to install supplementary
               air-conditioning units in the Premises and the expense of
               installation, operation and maintenance of any such supplementary
               units shall be paid by Tenant to Landlord as Additional Rent.

          (ii) Electricity solely for the lighting fixtures in the Premises of
               up to three (3) watts per square foot of rentable area within the
               Premises, together with adequate electrical wiring and facilities
               to the Premises for standard building lighting fixtures and for
               Tenant's incidental uses. Distribution within the Premises is at
               Tenant's expense, although Tenant may use any existing conduit
               system within the Premises. All electricity used in the Premises
               other than for lighting fixtures shall be separately metered by a
               meter or meters to be installed at Landlord's expense. Tenant
               agrees to pay for such electricity directly to the utility
               providing such electricity. Tenant shall bear the cost of
               providing all light fixtures and replacement of all lamps, tubes,
               ballasts and starters for lighting fixtures. With respect to such
               incidental uses, adequate electrical wiring and facilities will
               be furnished up to the meter in the Premises by Landlord,
               provided that: (a) the connected electrical load of the
               incidental use equipment does not


                                       11

<PAGE>

               exceed an average of two (2) watts per square foot of rentable
               area within the Premises; (b) the electricity for incidental uses
               will be at a nominal one hundred twenty (120) volts and no
               electrical circuit for the supply of such incidental use will
               have a current capacity exceeding twenty (20) amperes with a load
               not exceeding sixteen (16) amperes; and (c) such electricity will
               be used only for equipment and accessories normal to office
               usage. If Tenant's requirements for electricity for incidental
               uses exceed those set forth in the preceding sentence, Landlord
               reserves the right to require Tenant to install the conduit,
               wiring and other equipment necessary to supply electricity for
               such excess incidental use requirements at Tenant's expense by
               arrangement with Commonwealth Edison Company or another approved
               local utility. If Tenant's actual usage of electricity for
               lighting exceeds two (2) watts per square foot, then Landlord may
               charge and collect from Tenant a fee for such excess usage, the
               amount of such fee to be determined by Landlord. With respect to
               electricity for lighting, electricity for two hundred sixty (260)
               hours of lighting per month will be provided by Landlord as part
               of Operating Expenses. Tenant shall be billed monthly for all
               overtime hours of lighting in excess of two hundred sixty (260)
               hours per month.

          (iii) City water from the regular Building outlets for drinking,
               lavatory and toilet purposes. Upon execution by Landlord and
               Tenant of the "Condenser Water Addendum" attached hereto as
               Exhibit E, Landlord agrees to make available to Tenant
               supplemental condenser water as therein provided. If Landlord and
               Tenant have not executed the Condenser Water Addendum, then
               Landlord shall not have any obligation to provide Tenant with
               supplemental condenser water.

          (iv) Janitorial services as generally provided in first-class office
               buildings in downtown Chicago.

          (v)  Window washing of the inside and outside of those windows in the
               Building's perimeter walls which are situated in the Premises,
               weather permitting, at intervals to be determined by Landlord,
               but in no event less than two (2) times per Calendar Year with
               respect to the inside of said windows and no less than three (3)
               times per calendar year with respect to the outside of said
               windows.

          (vi) Adequate automatic passenger elevator service. Tenant shall have
               access to the Building 24 hours a day, 7 days a week, 365 days a
               year, subject to the other terms and conditions of this Lease.

          (vii) Freight elevator services, Monday through Friday only, from 7
               a.m. to 5 p.m. from the first lower level of the Building to the
               level on which the Premises are located, subject to reasonable
               scheduling by Landlord. The use of freight elevators shall be
               subject to reasonable regulations promulgated by Landlord from
               time to time.


                                       12

<PAGE>

          (viii) Receiving room and loading dock services, on any Monday through
               Friday which is not a Holiday, from 8 a.m. to 4 p.m., subject to
               reasonable scheduling by Landlord. The use of the receiving room
               and loading dock shall be subject to reasonable regulations
               promulgated by Landlord from time to time.

          (ix) Tenant shall be provided with one (1) line on the Building
               directory for each 1,000 square feet of rentable area in the
               Premises.

     (b)  INTERRUPTION OF SERVICES. Except for the limited abatement of Rent
          upon a fire or casualty described in Section 11 and except as
          expressly provided in this Section 6(b), Tenant agrees that Landlord
          shall not be liable in damages, by abatement of Rent or otherwise, for
          failure to furnish or delay in furnishing any service, or for any
          diminution in the quality or quantity thereof, when such failure or
          delay or diminution is occasioned, in whole or in part, by repairs,
          replacements, or improvements, by any strike, lockout or other labor
          trouble, by inability to secure electricity, gas or other fuel, or
          water, at the Building after reasonable effort so to do, by any
          accident or casualty whatsoever, by act or default of Tenant or other
          parties, or by any cause beyond Landlord's reasonable control. Except
          in cases of emergency, Landlord shall give Tenant reasonable prior
          notice of any delay or diminution in any service and shall use
          reasonable efforts to minimize any inconvenience to Tenant where such
          delay or diminution is the result of Landlord's voluntary actions.
          Such failures or delays or diminution shall never be deemed to
          constitute an eviction or disturbance of Tenant's use and possession
          of the Premises or relieve Tenant from paying Rent or performing any
          of its obligations under this Lease. If Landlord ceases to furnish any
          of the services referred to in this Section 6 or such ---------
          services are interrupted, and if (i) such cessation does not arise as
          a result of an act or omission of Tenant, (ii) such cessation does not
          arise as a result of a matter or condition affecting two or more city
          blocks, such as a city-wide power outage, (iii) as a result of such
          cessation, the Premises or any material portion thereof is rendered
          untenantable (meaning for the purposes of this Section 6(b) a lack of
          elevator access or Tenant's inability to use the -------------
          Premises or such material portion thereof in the normal course of its
          business) and Tenant in fact so ceases to use the Premises or such
          material portion thereof for the normal conduct of its business, and
          (iv) such cessation continues for a period of five (5) business days,
          then, the Rent payable hereunder shall be equitably abated based upon
          the percentage of the space in the Premises so rendered untenantable
          and not being used by Tenant. The foregoing abatement of Rent shall
          become effective as of the first business day following the day the
          Premises or such material portion thereof becomes untenantable and
          Tenant ceases to use such space for the normal conduct of its
          business.

     (c)  CHARGES FOR SERVICES. Charges for any service for which Tenant is
          required to pay, from time to time hereunder, including but not
          limited to hoisting services or after hours heating or air
          conditioning shall be due and payable at the same time as the
          installment of Rent with which they are billed, or if billed
          separately, shall be due and payable within thirty (30) days after
          such billing. If Tenant shall fail to make payment for any such
          services within five (5) days following Landlord's


                                       13

<PAGE>

          written demand therefor (which demand shall be in addition to the
          original billing therefor), Landlord may, without further notice to
          Tenant, discontinue any or all of such additional services until
          Tenant pays all amounts due, and such discontinuance shall not be
          deemed to constitute an eviction or disturbance of Tenant's use and
          possession of the Premises or relieve Tenant from paying Rent or
          performing any of its other obligations under this Lease.

     (d)  ENERGY/NATURAL RESOURCES CONSERVATION. Notwithstanding anything to the
          contrary in this Section 6 or elsewhere in this Lease, Landlord shall
          have the right to institute such policies, programs and measures as
          may be reasonably necessary for the conservation, recycling and/or
          preservation of energy and natural resources or energy or natural
          resource related services, or as may be required to comply with any
          applicable codes, rules and regulations, whether mandatory or
          voluntary. Any such voluntary policies, programs and measures taken by
          Landlord shall not materially adversely affect the level of services
          provided to Landlord pursuant to this Section 6.

     (e)  BILLING FOR ELECTRICITY. Tenant shall pay for the use of the
          electrical service to the Premises for incidental uses as described
          above directly to the utility company supplying electricity to the
          Premises based upon the existing separate metering and billing. Tenant
          shall be billed directly by such utility company and Tenant agrees to
          pay each bill promptly in accordance with its terms. In the event that
          Tenant cannot be billed directly, Landlord shall forward to Tenant
          each bill received by it with respect to such electrical usage in the
          Premises and Tenant shall pay it promptly in accordance with its
          terms.

     (f)  SECURITY. Landlord and Tenant recognize the existence of certain
          societal problems which, depending on the circumstances at the time,
          may necessitate the employment of certain security measures in the
          day-to-day operation of the Premises and Building. Tenant hereby
          agrees to the exercise by Landlord and its agents of such security
          measures, including but not limited to, the search of all persons
          entering or leaving the Building, the evacuation of the Building for
          cause, suspected cause, or for drill purposes, the denial of any
          access to the Building, and other similarly related actions that
          Landlord deems necessary to prevent any threat of property damage or
          bodily injury. Notwithstanding anything herein to the contrary, the
          exercise of such security measures by Landlord and the resulting
          interruption of service and/or cessation of Tenant's business, if any,
          shall never be deemed an eviction or disturbance of Tenant's use and
          possession of the Premises, or any part thereof, or render Landlord
          liable to Tenant for any resulting damages, or relieve Tenant from
          paying Rent or performing any of its obligations under this Lease. In
          the event the Building is closed and Tenant is unable to (and ceases
          to) conduct its business therein, and if (i) such cessation does not
          arise as a result of an act or omission of Tenant, (ii) such cessation
          does not arise as a result of a matter or condition affecting two (2)
          or more city blocks, (iii) such cessation continues for a period of
          five (5) business days, and (iv) Landlord's rent interruption
          insurance covers the event causing the closing of the Building, then
          Rent payable hereunder shall be equitably abated based upon the
          percentage of space in the Premises rendered untenantable and not
          being used by Tenant. The


                                       14

<PAGE>

          foregoing abatement of Rent shall become effective as of the first
          business day following the day the Premises becomes untenantable and
          Tenant ceases to use such space for the normal conduct of its
          business.

          Tenant agrees to cooperate with Landlord in complying with the
          obligations set forth in the City of Chicago High Rise Building
          Emergency Procedures Ordinance (the "Ordinance") and any and all
          similar laws and ordinances and the rules and regulations promulgated
          pursuant thereto and Tenant agrees to make the necessary personnel of
          Tenant available to fulfill the "tenant" obligations under the
          aforesaid Ordinance, including, without limitation, those of the Fire
          Wardens and Emergency Evacuation Teams (as such terms are defined in
          the Ordinance).

7.   REPAIRS

     (a)  Landlord shall, as part of Operating Expenses, keep the common areas
          of the Building (including, without limitation, all concourses,
          pedestrian passageways, elevator lobbies and restrooms on multi-tenant
          floors), the roof, foundation, structural elements of the Building and
          those portions of the mechanical, electrical, plumbing, HVAC, life
          safety, and other systems serving both the Premises and other areas of
          the Building in good order, repair and condition, including
          replacement or repair of all damaged or broken fixtures and
          appurtenances, at all times during the Term.

     (b)  Except as provided in Paragraph 7(a) above, Tenant will, at Tenant's
          own expense, keep the Premises in good order, repair and condition at
          all times during the Term, subject to reasonable wear and tear, and
          Tenant shall promptly and adequately repair all damage to the Premises
          and replace or repair all damaged or broken fixtures and appurtenances
          included in the Premises, under the supervision and subject to the
          approval of the Landlord, and within any reasonable period of time
          specified by the Landlord. If Tenant does not do so, Landlord may, but
          need not, after written notice to Tenant make such repairs and
          replacements, and Tenant shall pay Landlord the reasonable cost
          thereof plus a coordination fee payable to Landlord in connection with
          each such repair and/or replacement equal to: (i) fifteen percent
          (15%) of the actual total cost of any such repair or replacement
          costing $10,000 or less; (ii) ten percent (10%) of the actual total
          cost of any such repair or replacement costing more than $10,000 but
          less than or equal to $20,000; and (iii) five percent (5%) of the
          actual total cost of any such repair or replacement costing in excess
          of $20,000. Tenant shall pay such costs and fee within twenty (20)
          days after being billed therefor. Landlord may, but shall not be
          required to, enter the Premises at all reasonable times to make such
          repairs, alterations, improvements, installations and additions to the
          Premises or to the Building or to any equipment located in the
          Building as Landlord shall desire or deem necessary or as Landlord may
          be required to do by governmental authority or court order or decree.
          Landlord shall, except in the event of emergency, give reasonable
          advance written notice of any such entry, which notice shall describe
          the nature, extent and duration of the proposed work. Landlord shall
          use reasonable efforts to minimize any interference with Tenant's
          business.


                                       15

<PAGE>

8.   ADDITIONS AND ALTERATIONS

     (a)  Tenant shall not, without the prior written consent of Landlord, make
          any alterations, improvements, installations or additions to the
          Premises, which involve or affect the mechanical, electrical,
          structural, life safety or other common systems of the Building. If
          Tenant desires to perform decorating, painting or other work in the
          Premises which does not involve or affect such systems, Tenant shall
          provide Landlord with prior written notice thereof generally
          describing the work to be done. Landlord shall notify Tenant of its
          consent to any alterations, improvements, installations or additions
          which require Landlord's consent as soon as reasonably possible after
          Tenant's notice to Landlord of Tenant's intention to perform such work
          on the Premises. Landlord's consent shall not be withheld, conditioned
          or delayed (in each case, except as otherwise provided in this Lease)
          so long as such alterations, improvements, installations and additions
          (i) are consistent with the permitted uses of the Premises set forth
          in the Schedule to the Lease, (ii) do not adversely affect the
          mechanical, electrical, structural, life safety or other common
          systems of the Building, (iii) are in compliance with all applicable
          laws and other governmental or insurance company rules and
          regulations, and (iv) are not in conflict in any respect with
          Landlord's own contracts, contractor or union agreements. If Landlord
          consents to said alterations, improvements, installations or
          additions, it may impose such conditions with respect thereto as
          Landlord deems appropriate, including, without limitation, requiring
          Tenant to furnish Landlord with security for the payment of all costs
          to be incurred in connection with such work if such amount exceeds
          $500,000, insurance against liabilities which may arise out of such
          work, plans and specifications plus permits necessary for such work
          and, following completion, "as-built" drawings showing the actual
          location of said alterations, improvements, installations and
          additions. All work performed by Tenant shall be done in accordance
          with the Tenant/Contractor and Vendor Guidelines attached hereto as
          Exhibit B. That portion of any alterations, improvements,
          installations or additions to the Premises which involves or affects
          the mechanical, electrical, structural, life safety or other common
          systems of the Building shall be done at Tenant's expense by
          contractors hired by Landlord and selected by Tenant from Landlord's
          list of approved contractors which list shall include at least three
          (3) contractors for each trade who shall competitively price such
          work. Any other portions of such work may be performed at Tenant's
          expense by contractors hired and selected by Tenant, provided such
          contractors are approved in advance by Landlord, such approval not to
          be unreasonably withheld or delayed. Landlord shall not unreasonably
          delay or interfere with the performance of such work. Tenant shall
          promptly pay to Landlord or the Tenant's contractors, as the case may
          be, when due, the cost of all such work plus, in all cases requiring
          Landlord's consent, reimbursement to Landlord for all actual
          out-of-pocket expenses incurred by Landlord (including reasonable
          charges for time spent by employees of Landlord or its agents) in
          connection with such improvement, installation, alteration and/or
          addition. Tenant shall pay such costs within thirty (30) days after
          being billed therefor.

     (b)  All alterations, improvements, installations and additions to the
          Premises, whether temporary or permanent in character, made or paid
          for by Landlord or Tenant, shall without compensation to Tenant become
          Landlord's property at the


                                       16

<PAGE>

          termination of this Lease by lapse of time or otherwise and shall,
          unless Landlord is entitled to and does request their removal (in
          which case Tenant shall remove the same as provided in Section 16), be
          relinquished to Landlord in good condition, ordinary wear and damage
          resulting from fire or other casualty excepted. Landlord shall not be
          entitled to request that Tenant remove any alterations, improvements,
          installations and additions to the Premises, unless Landlord has
          notified Tenant in writing, pursuant to Tenant's prior written request
          given in connection with the approval of plans for such items, that
          Landlord will reserve the right to require Tenant to remove such
          alterations, improvements, installations and additions to the
          Premises.

9.   COVENANT AGAINST LIENS

     Tenant has no authority or power to cause or permit any lien or encumbrance
     of any kind whatsoever, whether created by act of Tenant, operation of law
     or otherwise, to attach to or be placed upon Landlord's title or interest
     in the Land, Building or Premises, and any and all liens and encumbrances
     created by Tenant shall attach to Tenant's interest only. Tenant covenants
     and agrees not to suffer or permit any lien of mechanics or materialmen or
     others to be placed against the Land, Building or Premises or any
     improvement in the Premises (whether installed or paid for by Landlord or
     Tenant) with respect to work or services claimed to have been performed for
     or materials claimed to have been furnished to Tenant or the Premises and,
     if any such lien attaches or a claim for a lien is asserted, Tenant
     covenants and agrees to cause it to be immediately released and removed of
     record; provided, however, that if such lien is being contested in good
     faith by Tenant by appropriate proceedings diligently pursued, Tenant shall
     not be in default hereunder if Tenant shall, in a manner subject to
     Landlord's prior written approval (which approval may be withheld
     arbitrarily) cause such lien or claim of lien to be insured over by a title
     insurance company selected by Landlord (which title insurance shall, in any
     event, inure to the benefit of Landlord, Landlord's mortgagees and any
     potential purchasers of the Land or Building of which Tenant shall be
     notified), and provided that, in any event, such lien or claim of lien
     shall be released or removed within four (4) months of the date such lien
     first attached. If such lien is not immediately released and removed or
     insured over as aforesaid, Landlord, at its sole option, may take all
     action necessary to release and remove such lien (without any duty to
     investigate the validity thereof) and Tenant shall promptly upon notice
     reimburse Landlord for all sums, costs and expenses (including reasonable
     attorney's fees) incurred by Landlord in connection with such lien.

     Notwithstanding anything in this Lease to the contrary, Tenant covenants
     and agrees not to suffer or permit any equipment lien to attach to any of
     the fixtures or improvements in the Premises, whether installed and/or paid
     for by Landlord or Tenant.

     Notwithstanding anything in this Lease to the contrary, except as set forth
     in Section 16 hereof, Landlord hereby waives any lien that Landlord may
     have on Tenant's personal property.

10.  INSURANCE

     (a)  WAIVER OF SUBROGATION. Landlord and Tenant each hereby waive any and
          every claim for recovery from the other for any and all loss of or
          damage to the Building


                                       17

<PAGE>

          or Premises or to the contents thereof, which loss or damage is
          covered by valid and collectible physical damage insurance policies,
          it being understood and agreed that the foregoing waiver shall also
          apply to the deductible under any such policy. Landlord waives any and
          every claim against Tenant for any and all loss of or damage to the
          Building or the Premises or the contents thereof which would have been
          covered had the insurance policies required to be maintained by
          Landlord by this Lease been in force, to the extent that such loss or
          damage is recoverable or would have been recoverable under such
          insurance policies. Tenant waives any and every claim against Landlord
          for any and all loss of or damage is recoverable or to the Building or
          the Premises or the contents thereof which would have been covered had
          the insurance policies required to be maintained by Tenant by this
          Lease been in force, to the extent that such loss or damage is
          recoverable or would have been recoverable under such insurance
          policies. Inasmuch as this mutual waiver will preclude the assignment
          of any such claim by subrogation (or otherwise) to an insurance
          company (or any other person), Landlord and Tenant each agree to give
          to each insurance company which has issued, or in the future may
          issue, to it policies of physical damage insurance, written notice of
          the terms of this mutual waiver, and to have said insurance policies
          properly endorsed, if necessary, to prevent the invalidation of said
          insurance coverage by reason of said waiver.

     (B)  COVERAGE. Tenant shall purchase and maintain insurance during the
          entire Term for the benefit of Tenant and Landlord (as their interest
          may appear) with terms, coverages and in companies reasonably
          satisfactory to Landlord, and with such increases in limits as
          Landlord may from time to time reasonably request, but initially
          Tenant shall maintain the following coverages in the following
          amounts:

          (i)  Commercial General Liability Insurance naming Landlord,
               Landlord's management, leasing and development agents and any
               mortgagees designated by Landlord as additional insureds, with
               coverage for premises/operations, personal and advertising
               injury, products/completed operations and contractual liability
               with combined single limits of liability of not less than
               $5,000,000 for bodily injury and property damage per occurrence.
               Host Liquor Insurance, naming Landlord, Landlord's management,
               leasing and development agents and any mortgagees designated by
               Landlord as additional insureds covering any liability that might
               arise from the provision or use of alcoholic beverages by Tenant
               on the Premises in an amount reasonably satisfactory to Landlord
               from time to time in light of statutory limits.

          (ii) Property Insurance covering all Tenant improvements in the
               Premises, office furniture, trade fixtures, office equipment,
               merchandise and all items of Tenant's property on the Premises,
               which insurance shall, with respect only to Tenant improvements,
               name Landlord, and any mortgagees designated by Landlord as
               additional insureds as their interests may appear. Such insurance
               shall be written on an "all risks" of physical loss or damage
               basis including but not limited to the perils of fire, extended
               coverage, windstorm, vandalism, malicious mischief, sprinkler
               leakage,


                                       18

<PAGE>

               flood and earthquake, for the full replacement cost value of the
               covered items and in amounts that meet any co-insurance clause of
               the policies of insurance and shall contain a commercially
               reasonable deductible amount.

          (iii) Workers' Compensation Insurance with statutory benefits and
               Employers Liability Insurance with the following amounts: Each
               Accident - $500,000; Disease - Policy Limit - $500,000; Disease -
               Each Employee - $500,000.

          Tenant shall, prior to the commencement of the Term and on each
          anniversary of the Commencement Date, furnish to Landlord certificates
          evidencing such coverage, which certificates shall state that such
          insurance coverage may not be changed or cancelled without at least
          thirty (30) days prior written notice to Landlord and Tenant. The
          insurance maintained by Tenant shall be deemed to be primary insurance
          and any insurance maintained by Landlord shall be deemed secondary
          thereto.

     (c)  AVOID ACTION INCREASING RATES. Tenant shall comply with all applicable
          laws and ordinances, all orders and decrees of court and all
          requirements of other governmental authorities, and shall not,
          directly or indirectly, make any use of the Premises (other than the
          Permitted Use) which may thereby be prohibited or be dangerous to
          person or property or which may jeopardize any insurance coverage or
          may increase the cost of insurance or require additional insurance
          coverage. If Tenant fails to comply with the provisions of this
          Section 10(c) and: (i) any insurance coverage is jeopardized and
          Tenant fails to correct such dangerous or prohibited use following
          notice within the applicable cure period set forth in Section 22
          hereof; or (ii) insurance premiums are increased and Tenant fails,
          following notice, to cease such use within the applicable cure period
          set forth in Section 22 hereof, then in each event such failure shall
          constitute a Default by Tenant hereunder and Landlord shall have all
          of its remedies as set forth in this Lease.

     (d)  INSURANCE MAINTAINED BY LANDLORD. Landlord agrees to maintain property
          insurance insuring the Building for the full replacement cost thereof
          (excluding the cost of excavations, foundations and footings below the
          lowest basement level and excluding coverage for acts of terrorism or
          other occurrences, the cost of which coverage makes it commercially
          unreasonable to purchase in Landlord's reasonable judgment) and
          commercial general liability insurance in amounts not less that
          $25,000,000.00.

11.  FIRE OR CASUALTY

     (a)  Section 7 hereof notwithstanding, if the Premises or the Building
          (including machinery or equipment used in its operation) shall be
          damaged by fire or other casualty and if such damage does not cause a
          termination of this Lease as described in the following sentences,
          then Landlord shall repair and restore the damage with reasonable
          promptness, subject to reasonable delays for insurance adjustments and
          delays caused by matters beyond Landlord's reasonable control, but
          Landlord shall not be obligated to expend for repairing or restoring
          the


                                       19

<PAGE>

          damage an amount in excess of the proceeds of insurance recovered with
          respect to the damage. Landlord shall give notice to Tenant within one
          hundred twenty (120) days after such fire or other casualty of
          Landlord's reasonable estimate of the time required to complete all
          repairs and restorations. If in Landlord's estimate the Premises
          cannot be restored within one hundred eighty (180) days from the date
          of such fire or casualty, or if the casualty occurs within the last
          Lease Year and the Premises would take more than ninety (90) days to
          repair, then Tenant may elect in writing within sixty (60) days
          following the date of such notice from Landlord to terminate this
          Lease effective as of the date of Tenant's notice. If any such damage:
          (i) renders three (3) or more floors of the Building untenantable; or
          (ii) renders general Building systems inoperable and such systems
          cannot be repaired in Landlord's reasonable estimate within one
          hundred eighty (180) days from the date of such damage, or (iii)
          occurs within the last two (2) Lease Years, Landlord shall have the
          right to terminate this Lease as of the date of such damage upon
          giving written notice to the Tenant at any time within one hundred
          twenty (120) days after the date of such damage. Landlord shall have
          no liability to Tenant, and Tenant shall not be entitled to terminate
          this Lease, by virtue of any delays in completion of such repairs and
          restoration. Rent, however, shall abate on those portions of the
          Premises as are, from time to time, untenantable as a result of such
          damage. If Tenant does not elect to terminate this Lease as provided
          above and Landlord commences repairs and restoration but fails to
          substantially complete the necessary repairs and restoration within
          one hundred twenty (120) days from the estimated date of completion of
          the repairs and restoration, then Tenant may give Landlord written
          notice of Tenant's election to terminate this Lease effective as of a
          date thirty (30) days after Tenant's notice if the repairs and
          restorations are not substantially completed by such date.

     (b)  Notwithstanding anything to the contrary herein set forth, Landlord
          shall have no duty pursuant to this Section 11 to repair or restore
          any alterations, additions, installations or improvements in the
          Premises or the decorations thereto except to the extent that the
          proceeds of the insurance carried by Tenant are timely received by
          Landlord. If Tenant desires any other or additional repairs or
          restoration, and if Landlord consents thereto, it shall be done at
          Tenant's sole cost and expense subject to all of the provisions of
          Sections 7 and 8 hereof. Tenant acknowledges that Landlord shall be
          entitled to the full proceeds of any insurance coverage, whether
          carried by Landlord or Tenant, for damage to any alterations,
          additions, installations or improvements which would become Landlord's
          property upon the termination of this Lease.

12.  WAIVER OF CLAIMS - INDEMNIFICATION

     To the extent not prohibited by law and subject to the waiver of
     subrogation contained in Section 10(a), Landlord and its partners,
     affiliates, officers, agents, servants and employees shall not be liable
     for any damage either to person, property or business or resulting from the
     loss of use thereof sustained by Tenant or by other persons due to the
     Building or any part thereof or any appurtenances thereto becoming out of
     repair, or due to the happening of any accident or event in or about the
     Building, including the Premises, or due to any act or neglect of any
     tenant or occupant of the Building or of any


                                       20

<PAGE>

     other person, unless caused by the negligence or willful misconduct of
     Landlord or its agents, employees or contractors. This provision shall
     apply particularly, but not exclusively, to damage caused by gas,
     electricity, snow, ice, frost, steam, sewage, sewer gas or odors, fire,
     water or by the bursting or leaking of pipes, faucets, sprinklers, plumbing
     fixtures and windows, and, except as provided above, shall apply without
     distinction as to the person whose act or neglect was responsible for the
     damage and shall apply whether the damage was due to any of the causes
     specifically enumerated above or to some other cause of an entirely
     different kind. Tenant further agrees that all personal property upon the
     Premises, or upon loading docks, receiving and holding areas, or freight
     elevators of the Building, shall be at the risk of Tenant only, and that
     Landlord shall not be liable for any loss or damage thereto or theft
     thereof. Without limiting any other provisions hereof, but subject to the
     provisions of Section 10(a) hereof, except for liability caused by the
     negligence or willful acts of Landlord or its agents, employees or
     contractors, Tenant agrees to defend, protect, indemnify and save harmless
     Landlord and its partners, affiliates, officers, agents, servants and
     employees from and against all liability to third parties arising out of
     the use of the Premises or the acts or omissions of Tenant or its servants,
     agents, employees, contractors, suppliers or workers.

     Except for liability caused by the negligence or willful acts or omissions
     of Tenant or Tenant's partners, affiliates, officers, agents, servants or
     employees and subject to Section 10(a) hereof, Landlord agrees to defend,
     protect, indemnify and save harmless Tenant and its partners, shareholders,
     directors, affiliates, officers, agents, servants, contractors and
     employees from and against all liability to third parties arising out of
     negligent acts or omissions of Landlord or its servants, agents, employees,
     contractors, suppliers or workers.

     The provisions of this Section 12 shall survive the expiration of the Term
     or earlier termination of this Lease or the termination of Tenant's right
     to possession of the Premises.

13.  NONWAIVER

     No waiver of any provision of this Lease shall be implied by any failure of
     either Landlord or Tenant to enforce any remedy on account of the violation
     of such provisions, even if such violation is continued or repeated
     subsequently, and no express waiver shall affect any provision other than
     the one specified in such waiver and that one only for the time and in the
     manner specifically stated. No receipt of monies by Landlord from Tenant
     after the termination of this Lease shall in any way alter the length of
     the Term or of Tenant's right of possession hereunder or after the giving
     of any notice shall reinstate, continue or extend the Term or affect any
     notice given Tenant prior to the receipt of such monies, it being agreed
     that after the service of notice or the commencement of a suit or after
     final judgment for possession of the Premises, Landlord may receive and
     collect any Rent due, and the payment of said Rent shall not waive or
     affect said notice, suit or judgment.

14.  CONDEMNATION

     If any portion of the Premises or the Land or the Building shall be taken
     or condemned by any competent authority for any public or quasi-public use
     or purpose, Landlord shall have


                                       21

<PAGE>

     the right, exercisable at its sole discretion, to cancel this Lease upon
     not less than sixty (60) days notice prior to the date of cancellation
     designated in the notice. No money or other consideration shall be payable
     by Landlord to Tenant for the right of cancellation and Tenant shall have
     no right to share in the condemnation award or in any judgment for damages
     caused by such taking or condemnation. Nothing contained herein shall
     prevent Tenant from seeking its own award for moving expenses and loss of
     or damage to its personal property.

15.  ASSIGNMENT AND SUBLETTING

     (a)  Subject to any provisions of this Section 15 to the contrary, Tenant
          shall not, without the prior written consent of Landlord, which
          consent shall not be unreasonably withheld or delayed, (i) assign,
          convey or mortgage this Lease or any interest hereunder; (ii) permit
          to occur or permit to exist any assignment of this Lease, or any lien
          upon Tenant's interest, voluntarily or by operation of law; (iii)
          sublet the Premises or any part thereof; (iv) advertise as available
          for sublet or assignment all or any portion of the Premises, except
          that Tenant may advertise so long as such advertising is in keeping
          with a standard of professionalism and Landlord is given advance
          notice and copies of the advertisements; or (v) permit the use of the
          Premises by any parties other than Tenant and its employees. Any such
          action on the part of Tenant shall be void and of no effect. There
          shall be no partial assignment of Tenant's interest in this Lease, but
          Tenant may sublet portions of the Premises subject to the terms and
          conditions hereof. Notwithstanding anything contained herein to the
          contrary, Landlord shall not be deemed to have acted unreasonably in
          its election not to consent to any such action on the part of Tenant
          because (aa) a Default shall have occurred and be continuing under
          this Lease, (bb) the proposed assignee or sublessee (the "Proposed
          Tenant") shall be an existing tenant or occupant of the Building, (cc)
          such assignment or subletting shall cause Landlord to be in breach of
          any "exclusive use" or similar provision contained in any other lease
          for space in the Building (provided that such provision shall not be
          in conflict with the use provision set forth in the Schedule), (dd) in
          the reasonable judgment of Landlord, the Proposed Tenant is of a
          character or is engaged in a business which would be deleterious to
          the reputation of the Building, or the Proposed Tenant is not
          sufficiently financially responsible to perform its obligations under
          any such assignment or sublease, or the Proposed Tenant or any of its
          partners, members, shareholders, employees or affiliates, or the
          business conducted by any of them, could pose a security risk for the
          Building and/or its occupants, (ee) the portion of the Premises which
          Tenant proposes to sublease including the means of ingress and egress
          thereto and the proposed use thereof, and the remaining portion of the
          Premises will violate any city, state or federal law, ordinance or
          regulation, (ff) the Proposed Tenant is a government agency (or any
          subdivision thereof), (gg) the Proposed Tenant is a party with whom
          Landlord is then negotiating a lease for space in the Building (it
          being understood and agreed that at the time Tenant is intending to go
          to the market to assign the Lease or to sublet all or a portion of the
          Premises Tenant may request that Landlord identify those parties with
          whom Landlord is then negotiating a lease for space in the Building
          and Landlord shall do so provided Tenant and Tenant's broker agree to
          utilize such list on a confidential basis and agree not to share it
          with any parties who have no need to


                                       22

<PAGE>

          know), (hh) the portion of the Premises which Tenant proposes to
          assign or sublease does not consist of contiguous space, provided,
          however, that the foregoing are merely examples of the reasons for
          which Landlord may reasonably not consent to any such actions by
          Tenant and shall not be deemed exclusive of any reason for reasonably
          making such election, whether similar or dissimilar to the foregoing
          examples. The term "sublease" and all words derived therefrom, as used
          in this Section 15 shall include any subsequent sublease or assignment
          of such sublease and any other interest arising under such sublease.
          Landlord's consent to any assignment, subletting or transfer or
          Landlord's election to accept any assignee, subtenant or transferee as
          the Tenant hereunder and to collect rent from such assignee, subtenant
          or transferee shall not release Tenant or any subsequent Tenant from
          any covenant or obligation under this Lease, and Tenant further
          expressly acknowledges and agrees that any renewal rights, expansion
          rights, reduction rights, rights of first offer or termination rights
          shall be deemed personal to the original Tenant and shall not inure to
          the benefit of any assignee, subtenant or transferee taking from the
          original Tenant. Landlord's consent to any assignment, subletting or
          transfer shall not constitute a waiver of Landlord's right to withhold
          its consent to any future assignment, subletting, or transfer.
          Landlord may condition its consent upon execution by the subtenant or
          assignee of an instrument confirming such restrictions on further
          subleasing or assignment and joining in the waivers and indemnities
          made by Tenant hereunder insofar as such waivers and indemnities
          relate to the affected space. Without limiting the foregoing, Tenant
          agrees to indemnify, defend and hold Landlord and its employees,
          agents, their officers and partners harmless from and against any
          claims made by any broker or finder for a commission or fee in
          connection with any subleasing or assignment by Tenant or any
          subtenant or assignee of Tenant.

     (b)  If Tenant desires the consent of Landlord to an assignment or
          subletting or in the event Tenant desires to assign or sublet the
          Premises to Permitted Assignees (as hereinafter defined) where
          Landlord's consent is not required pursuant to Section 15(f) below,
          Tenant shall submit to Landlord, at least thirty (30) days prior to
          the proposed effective date of the assignment or sublease, a written
          notice which includes:

          (i)  All documentation then available related to the proposed sublease
               or assignment; and

          (ii) Sufficient information to permit Landlord to determine the
               identity and character of the proposed subtenant or assignee and
               the financial condition of the proposed assignee or subtenant.

               Landlord agrees to notify Tenant as to whether Landlord consents
          to such assignment or sublease within thirty (30) days after receipt
          by Landlord of all documents required pursuant to (i) and (ii) above;
          provided, however, that copies of the final executed documentation
          must be supplied to Landlord by Tenant at least ten (10) business days
          prior to the effective date of such assignment or sublease and
          Landlord shall have an additional ten (10) business days after receipt
          of such revised documents, or the remainder of the original thirty
          (30) day period,


                                       23

<PAGE>

          whichever is longer, to either approve or disapprove of such
          assignment or sublease. If the terms of the proposed sublease or
          assignment change in any material respect from the terms contained in
          the documents previously delivered to Landlord pursuant to this
          subparagraph, or the identity of the sublessee or assignee changes,
          then Tenant shall resubmit the documentation to Landlord indicating
          the changes and Landlord shall have an additional thirty (30) days to
          either approve or disapprove of such assignment or sublease.

     (c)  In addition to withholding its consent Landlord shall have the right
          to terminate this Lease in the event of a proposed assignment of this
          Lease or a proposed sublease of the entire Premises or to terminate
          this Lease as to that portion of the Premises which Tenant seeks to
          sublet, if Tenant seeks to sublease less than the entire Premises.
          Landlord may exercise such right to terminate by giving written notice
          to Tenant no later than ten (10) business days after Landlord receives
          all of the information required by Section 15(b) above. If Landlord
          exercises its right to terminate, the Lease or portion thereof shall
          be deemed terminated effective as of, Landlord shall be entitled to
          recover possession of and Tenant shall surrender such portion of the
          Premises on the proposed date for possession by such assignee or
          subtenant.

     (d)  If Landlord consents to any assignment of this Lease or a sublease of
          the Premises, as a condition of Landlord's consent, Tenant shall pay
          to Landlord any reasonable attorneys' fees and expenses incurred by
          Landlord in connection with such assignment or sublease plus fifty
          percent (50%) of all Sublease Profits (as defined below) derived by
          Tenant from such assignment or sublease. "Sublease Profits" shall mean
          the entire excess (after deducting all reasonable costs of subletting)
          of revenues generated by the assignment of this Lease or the
          subleasing of the Premises over the Rent applicable thereto. All such
          revenues shall be applied first to reimbursement of such costs of
          subletting or assigning until they are paid in full. Tenant shall
          furnish Landlord with a sworn statement, certified by an officer of
          Tenant, setting forth in detail the computation of Sublease Profits,
          and Landlord, or its representatives, shall have access to the books,
          records and papers of Tenant in relation thereto, and to make copies
          thereof. If a part of the consideration for such assignment shall be
          payable other than in cash, the payment to Landlord shall be payable
          in accordance with the foregoing percentage of the cash and other
          non-cash considerations in such form as is reasonably satisfactory to
          Landlord. Such percentage of Sublease Profits shall be paid to
          Landlord promptly by Tenant upon Tenant's receipt from time to time of
          periodic payments from such assignee or subtenant or at such other
          time as Tenant shall realize Sublease Profits from such assignment or
          sublease. If such sublease or assignment is part of a larger
          transaction in which other assets of Tenant are being transferred, the
          consideration for the assignment or sublease shall be a reasonable
          allocation of the total value received minus a reasonable allocation
          of the total expenses incurred in connection with such transaction.

     (e)  If Tenant is a partnership, a withdrawal or change, whether voluntary,
          involuntary or by operation of law or in one or more transactions, of
          partners owning directly or indirectly a controlling interest in
          Tenant shall be deemed an assignment of this


                                       24

<PAGE>

          Lease and subject to the provisions of this Section 15. If Tenant is a
          corporation, any dissolution, merger, consolidation or other
          reorganization of Tenant, or the sale, transfer or redemption of a
          direct or indirect controlling interest in the capital stock of
          Tenant, in one or more transactions, shall be deemed a voluntary
          assignment of this Lease and subject to the provisions of this Section
          15. For purposes hereof "control" shall mean possession, directly or
          indirectly, of the power to direct, or cause the direction of, the
          management and policies of such corporation or other business entity
          through the ownership of voting, securities, by contract, or
          otherwise. Neither this Lease nor any interest therein nor any estate
          created thereby shall pass by operation of law or otherwise to any
          trustee, custodian or receiver in bankruptcy of Tenant or any assignee
          for the assignment of the benefit of creditors of Tenant.

     (f)  Notwithstanding anything contained in this Section 15 to the contrary
          (including, without limitation, Section 15(c) above), Tenant shall
          have the right, upon prior written notice to Landlord but without
          Landlord's consent, to assign or sublet all of the Premises to
          Permitted Assignees (as hereinafter defined), provided that such
          assignment or subletting shall not relieve Tenant of its primary
          responsibility for the performance of all obligations of Tenant
          hereunder, and in the event of an assignment to a Permitted Assignee,
          such Permitted Assignee assumes, pursuant to an agreement in form and
          substance reasonably satisfactory to Landlord, the obligations of
          Tenant hereunder and in the event of a sublet, such sublet is governed
          by a form of sublease reasonably approved in advance by Landlord. As
          used herein, a "Permitted Assignee" shall mean (i) any entity owned or
          controlled by Tenant, (ii) any entity of which Tenant is a subsidiary
          (on any level), (iii) any entity which is under common ownership or
          control with Tenant, (iv) any entity into which Tenant is merged or
          consolidated or which consolidates into Tenant, or (v) any entity
          which acquires all or substantially all of the asset or stock of
          Tenant, provided in each case that Landlord is reasonably satisfied
          with the business reputation and financial condition of such entity,
          it being understood that if such entity has a net worth at least equal
          to that of Tenant on the date hereof, the financial condition of such
          entity shall be deemed satisfactory to Landlord. At least ten (10)
          business days prior to the effective date of such assignment or
          sublease, Tenant agrees to deliver to Landlord documentation
          evidencing that Landlord does not have the right to consent to such
          transaction pursuant to this Section 15(f). Further, Tenant agrees to
          deliver to Landlord, within ten (10) business days prior to the
          effective date of such assignment or sublease, fully executed copies
          of the documents effectuating such assignment or sublease.

16.  SURRENDER OF POSSESSION

     Upon the expiration of the Term or upon the termination of Tenant's right
     of possession, whether by lapse of time or at the option of Landlord as
     herein provided, Tenant shall forthwith surrender the Premises to Landlord
     in good order, repair and condition, ordinary wear excepted and shall, if
     Landlord so requires, remove those items which Landlord has previously
     identified as being subject to removal as described in Section 8(b) hereof.
     Any interest of Tenant in the alterations, improvements, installations and
     additions to the Premises made or paid for by Landlord or Tenant shall,
     without


                                       25

<PAGE>

     compensation to Tenant, become Landlord's property at the termination of
     this Lease by lapse of time or otherwise and such alterations,
     improvements, installations and additions shall be relinquished to Landlord
     in good condition, ordinary wear excepted. Prior to the termination of the
     Term or of Tenant's right of possession Tenant shall remove its office
     furniture, trade fixtures, office equipment and all other items of Tenant's
     movable property on the Premises. Tenant shall not have any right to
     remove, unless requested to do so by Landlord pursuant to Section 8(b), any
     alterations, improvements, installations or additions, which shall include
     built-in furniture or shelves and all other attached items, excluding trade
     fixtures. Tenant shall pay to Landlord upon demand the cost of repairing
     any damage to the Premises and to the Building caused by any such removal.
     If Tenant fails or refuses to remove any such property from the Premises
     within five (5) days after written notice from Landlord, Tenant shall be
     conclusively presumed to have abandoned the same, and title thereto shall
     thereupon pass to Landlord without any cost either by set-off, credit,
     allowance or otherwise, and at its option Landlord may: (i) accept the
     title to the property; (ii) or at Tenant's expense remove the property or
     any part in any manner that Landlord shall choose, repairing any damage to
     the Premises caused by such removal; and store, destroy or otherwise
     dispose of the property without incurring liability to Tenant or any other
     person. During Tenant's move from the Premises, Tenant's agents,
     contractors, mechanics and movers shall work in harmony and not interfere
     with Landlord's or another tenant's agents, contractors and mechanics. If
     at any time Tenant's agents, contractors, mechanics or movers shall in the
     judgment of Landlord violate the Contractor & Vendor Guidelines attached to
     the Lease as Exhibit B, Landlord shall have the right to request that such
     agents, contractors, mechanics or movers immediately leave the Premises and
     Building.

17.  HOLDING OVER

     During each month or portion thereof for which Tenant shall retain
     possession of the Premises or any portion thereof after the expiration or
     termination of the Term or of Tenant's right of possession, whether by
     lapse of time or otherwise, Tenant shall pay to Landlord an amount as Rent
     equal to 175% of the Base Rent and 175% of the Additional Rent paid by
     Tenant during the previous month of the Term for all of the Premises
     (regardless of whether Tenant retains possession of all or only a portion
     of the Premises) for each month Tenant so retains possession of the
     Premises (regardless of whether Tenant retains possession of the Premises
     or a portion thereof for all or only a portion of such month).
     Notwithstanding the foregoing, to the extent (x) Tenant retains possession
     of all or a portion of the Premises located on the ninth (9th) floor of the
     Building, but does not retain possession of any portion of the Premises
     located on the tenth (10th) floor of the Building, or (y) Tenant retains
     possession of all or a portion of the Premises located on the tenth (10th)
     floor of the Building, but does not retain possession of any portion of the
     Premises located on the ninth (9th) floor of the Building, then Tenant
     shall be liable only for the aforesaid amounts as they relate to that
     portion of the Premises located on the ninth (9th) or tenth (10th) floor of
     the Building, as the case may be, but such calculation shall be made with
     regard to all of the Premises located on such floor regardless of whether
     Tenant holds over on all or a portion of the Premises located on such
     floor. Tenant shall also pay all damages sustained by Landlord on account
     of such holding over; provided, however, that Tenant shall not be liable
     for consequential damages unless Tenant holds over for thirty (30) days or
     more. The provisions of this Section 17 shall


                                       26

<PAGE>

     not be deemed to limit or constitute a waiver of any other rights or
     remedies of Landlord provided herein or at law.

18.  ESTOPPEL CERTIFICATE

     Tenant agrees, that, from time to time upon not less than twenty (20) days
     prior request by Landlord, Tenant, or Tenant's duly authorized
     representative having knowledge of the following facts, will deliver to
     Landlord a statement in writing certifying: (i) that this Lease is
     unmodified and in full force and effect (or if there have been
     modifications, a description of such modifications and that the Lease as
     modified is in full force and effect); (ii) the dates to which Rent and
     other charges have been paid; (iii) that the Landlord is not in default
     under any provision of this Lease, or, if in default, the nature thereof in
     detail; and (iv) such further matters as are set forth on the form of
     estoppel certificate attached hereto as Exhibit D and made a part hereof,
     or as may be reasonably requested by Landlord, it being intended that any
     such statement may be relied upon by any mortgagees or prospective
     mortgagees, or any prospective assignee of any Mortgagee, or any
     prospective and/or subsequent purchaser or transferee of all or a part of
     Landlord's interest in the Land and/or Building. Tenant shall execute and
     deliver whatever instruments may be required for such purposes within
     twenty (20) days following Landlord's request therefor.

19.  OBLIGATIONS TO MORTGAGEES

     (a)  SUBORDINATION. This Lease is subject and subordinate to all present
          and future ground or underlying leases of the Land and/or improvement
          leases of the Building and to the lien of any mortgages or trust deeds
          now and hereafter in force against the Land or Building and to all
          renewals, extensions, modifications, consolidation and replacements
          thereof. At Landlord's request (and after consent from any prior
          mortgagee or lessor if Tenant has agreed not to so subordinate without
          such consent), Tenant shall execute such further instruments or
          assurances as Landlord may deem necessary to evidence, confirm or
          effectuate such subordination of this Lease thereto or, if requested,
          to make Tenant's interest in this Lease superior thereto. If any
          mortgage shall be foreclosed or property encumbered thereby is
          transferred in lieu of foreclosure, or if any such future ground or
          improvements lease or underlying lease is terminated: (i) the
          liability of the mortgagee, trustee, transferee, purchaser at such
          foreclosure sale or ground lessor or improvements lessor and the
          liability of a subsequent owner (all of the foregoing parties are
          collectively referred to as "Mortgagee") shall exist only with respect
          to the period during which the Mortgagee is the owner of the Land or
          Building and the Mortgagee shall be released from any further
          liability upon its transfer of ownership; and (ii) the Mortgagee shall
          not have any liability whatsoever for the acts of the Landlord prior
          to any such transfer nor any liability for any deposits made by Tenant
          hereunder unless Mortgagee has received such deposits; and (iii)
          Tenant hereby agrees to attorn to and recognize as Landlord, Mortgagee
          or any successor lessor under the Master Lease (as hereinafter
          defined) and, upon request of the Mortgagee, will execute such
          instruments as may be required by said Mortgagee or successor lessor
          under the Master Lease. Landlord shall use reasonable efforts to
          obtain for Tenant a Subordination, Non-


                                       27

<PAGE>

          Disturbance and Attornment Agreement from the current Mortgagee on
          such Mortgagee's current form; provided, however, that Landlord's
          inability to obtain the same shall not give Tenant any rights to
          terminate this Lease or negate any of the provisions hereof; provided,
          further however, that notwithstanding anything herein to the contrary,
          this Lease shall not be subordinate to any future mortgagee or deed of
          trust unless the Mortgagee under such mortgage or deed of trust enters
          into a Subordination, Non-disturbance and Attornment Agreement with
          Tenant on such Mortgagee's then current form.

     (b)  NOTICE TO LANDLORD AND MORTGAGEE. If any act or omission by Landlord
          would give Tenant the right to damages from Landlord or any rights
          with respect to this Lease, Tenant will not sue for such damages or
          exercise any such rights until (i) it shall have given written notice
          of the act or omission to Landlord and to the holder(s) of the
          indebtedness or other obligations secured by any mortgage or deed of
          trust affecting the Premises or of any ground or underlying lease, if
          the name and address of such holder(s) have been furnished to Tenant
          within the last twelve (12)months or Mortgagee and Tenant have entered
          into a Subordination, Non-disturbance and Attornment Agreement as
          provided in Section 19(a) above; and (ii) a reasonable period of time
          (in light both of the time required to cure the act or omission and
          the effect of the act or omission on Tenant's business operations in
          the Premises) to cure the act or omission has elapsed following the
          giving of the notice, during which time Landlord and such holder(s),
          or either of them, their agents or employees, will be entitled to
          enter upon the Premises and do therein whatever may be necessary to
          cure the act or omission.

20.  CERTAIN RIGHTS RESERVED BY LANDLORD

     Landlord shall have the following rights, each of which Landlord may
     exercise without notice to Tenant (but subject to maintaining access to the
     Premises as described in subparagraph (iii) below), and without liability
     to Tenant for damage or injury to property, person or business on account
     of the exercise thereof, and the exercise of any such rights shall not be
     deemed to constitute an eviction or disturbance of Tenant's use or
     possession of the Premises and shall not give rise to any claim for set-off
     or abatement of rent or any other claim:

          (i)  To change the name or street address of the Building.

          (ii) To install, affix and maintain any and all signs on the exterior
               or interior of the Building.

          (iii) To decorate or to make repairs, alterations, additions,
               installations or improvements, whether structural or otherwise,
               in and about the Building, or any part thereof, and for such
               purposes to enter upon the Premises after providing advance
               written notice to Tenant (except in the event of an emergency),
               and during the continuance of any of said work, to temporarily
               close doors, entryways, public space and corridors in the
               Building and to interrupt or temporarily suspend services or use
               of facilities, all without affecting any of Tenant's obligations
               hereunder, so long as the


                                       28

<PAGE>

               Premises are reasonably accessible and usable. Landlord shall use
               reasonable efforts to minimize any interference with Tenant's
               business.

          (iv) To furnish door keys, magnetic cards or electronic access systems
               for the entry door(s) in the Premises at the commencement of the
               Lease and to retain at all times, and to use in appropriate
               instances, keys or access cards to all doors within and into the
               Premises. Tenant agrees to purchase only from Landlord additional
               keys and access cards as required, to change no locks, and not to
               affix locks on doors without the prior written consent of
               Landlord. Notwithstanding the provisions for Landlord's access to
               the Premises, Tenant relieves and releases Landlord of all
               responsibility arising out of theft, robbery, pilferage and
               personal assault, excluding negligence or willful misconduct of
               Landlord or its agents. Upon the expiration of the Term or
               Tenant's right to possession, Tenant shall return all keys and
               access cards to Landlord and shall disclose to Landlord the
               combination of any safes, cabinets or vaults left in the
               Premises.

          (v)  To designate and approve all window coverings used in the
               Building, including, without limitation, solar window coverings.

          (vi) To approve the weight, size and location of safes, vaults,
               vertical files and other heavy equipment and articles in and
               about the Premises and the Building so as not to exceed the legal
               live load per square foot designated by the structural engineers
               for the Building, and to require all such items and furniture and
               similar items to be moved into or out of the Building and
               Premises only at such times and in such manner as Landlord shall
               direct in writing. Tenant shall not install or operate machinery
               or any mechanical devices of any nature not directly related to
               Tenant's ordinary use of the Premises without the prior written
               consent of Landlord. Movements of Tenant's property into or out
               of the Building or Premises and within the Building are entirely
               at the risk and responsibility of Tenant, and Landlord reserves
               the right to require permits before allowing any property to be
               moved into or out of the Building or Premises.

          (vii) To establish reasonable controls for the purpose of regulating
               all property and packages, both personal and otherwise, to be
               moved into or out of the Building and Premises and all persons
               using the Building after normal office hours.

          (viii) To regulate in a reasonable manner delivery and service of
               supplies and the usage of the loading docks, receiving areas and
               freight elevators.

          (ix) To show the Premises to prospective lien holders and purchasers
               at reasonable times (after providing reasonable advance oral or
               written notice to Tenant), provided that Landlord shall use
               reasonable efforts to minimize any interference with Tenant's
               business and provided further that showings to prospective
               tenants shall only be permitted during the last two (2) Lease
               Years of the Term.


                                       29

<PAGE>

          (X)  To enter the Premises at any reasonable time to inspect the
               Premises (after providing reasonable advance oral or written
               notice to Tenant), provided that Landlord shall use reasonable
               efforts to minimize any interference with Tenant's business.

          (xi) If Landlord elects to make available to tenants in the Building
               any services or supplies (or arranges a master contract therefor)
               in the nature of messenger services or other operational/security
               features for the Building, Tenant agrees to obtain its
               requirements, if any, therefor from Landlord or under any such
               contract, provided that the charges therefor are reasonable, and
               that the services contracted for are similar to those provided in
               other buildings in downtown Chicago.

21.  RULES AND REGULATIONS

     Tenant agrees to observe the rules and regulations for the Building
     attached hereto as Exhibit C and made a part hereof. Landlord shall have
     the right from time to time to prescribe additional rules and regulations
     for general application to all office tenants which, in its reasonable
     judgment, may be desirable for the use, entry, operation and management of
     the Premises and Building, each of which rules and regulations and any
     amendments thereto shall become a part of this Lease. Tenant shall comply
     with all of the rules and regulations; provided, however, that the rules
     and regulations shall not contradict or abrogate any right or privilege
     herein expressly granted to Tenant.

22.  DEFAULT AND LANDLORD'S REMEDIES

     (a)  DEFAULT. Any one or more of the following events shall be a default
          ("Default") under this Lease: (i) If Tenant does not pay the Rent or
          any installment thereof or does not pay any other sum required to be
          paid by Tenant under this Lease or under the terms of any other
          agreement between Landlord (or Landlord's predecessors in title) and
          Tenant and such default shall continue for five (5) days after written
          notice to Tenant; or (ii) if Tenant fails to observe or perform any of
          the other covenants or conditions in this Lease which Tenant is
          required to observe and perform and such default shall continue for
          thirty (30) days after written notice to Tenant, provided, however, if
          such default does not involve a hazardous condition and is susceptible
          to cure but cannot, by the use of reasonable efforts, be cured within
          thirty (30) days, Landlord shall not exercise any of its remedies
          hereunder if and so long as (a) Tenant shall have commenced to cure
          such default within thirty (30) days and (b) Tenant shall thereafter
          continuously and diligently proceed to cure such default in a manner
          reasonably satisfactory to Landlord, and (c) such default shall be
          cured within one hundred twenty (120) days of such notice to Tenant;
          or (iii) if a default is made in the performance by Tenant of any
          covenant of this Lease which involves a hazardous condition and is not
          cured by Tenant immediately upon written notice to Tenant; or (iv) if
          the interest of Tenant in this Lease shall be levied on under
          execution or other legal process; or (v) if any voluntary petition in
          bankruptcy or for corporate reorganization or any similar relief shall
          be filed by Tenant; or (vi) if any involuntary petition in bankruptcy
          shall be filed against Tenant under any federal


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<PAGE>

          or state bankruptcy or insolvency act and shall not have been
          dismissed within ninety (90) days from the filing thereof; or (vii) if
          a receiver shall be appointed for Tenant or any of the property of
          Tenant by any court and such receiver shall not have been dismissed
          within ninety (90) days from the date of his appointment; or (viii) if
          Tenant shall make an assignment for the benefit of creditors; or (ix)
          if Tenant shall admit in writing Tenant's inability to meet Tenant's
          debts as they mature.

     (b)  LANDLORD'S REMEDIES. If a Default occurs, Landlord may, at its sole
          option, with or without further notice or demand of any kind to Tenant
          or any other person, have any one or more of the following described
          remedies in addition to all other rights and remedies provided at law
          or in equity or elsewhere herein (provided that Landlord shall use
          such efforts as are required by law to mitigate any damages resulting
          from such Default):

          (i)  Terminate this Lease and the Term created hereby, in which event
               Landlord may forthwith repossess the Premises. If Landlord does
               terminate this Lease and repossess the Premises, Landlord shall
               be entitled to recover forthwith, in addition to any other sums
               or damages for which Tenant may be liable to Landlord, as damages
               a sum of money equal to the greater of: (1) the excess of the
               present value of the Rent provided to be paid by Tenant for the
               balance of the Term over the present value of the anticipated
               fair market rent for the Premises (computed based upon the yield
               on U.S. Treasury obligations having a maturity closest to the
               Termination Date) that could be achieved for said period, after
               deduction of all anticipated expenses of reletting, including,
               without limitation, all allowances, abatements, brokerage
               commissions and other tenant concessions likely to be required
               under then-existing market conditions; or (2) the unamortized
               portion of any rent abatements, allowances, construction costs,
               brokerage commissions and other costs incurred by Landlord in
               connection with this Lease, as amortized on a straight-line basis
               with interest on the unamortized amount at twelve percent (12%)
               per annum over the portion of the Term during which Base Rent is
               payable. Should the present value of the anticipated fair market
               rent for the Premises, after deduction of all anticipated
               expenses of reletting, that could be achieved for the balance of
               the Term exceed the present value of the Rent provided to be paid
               by Tenant for the balance of the Term, Landlord shall have no
               obligation to pay to Tenant the excess or any part thereof or to
               credit such excess or any part thereof against any other sums or
               damages for which Tenant may be liable to Landlord.

          (ii) Landlord may terminate Tenant's right of possession and may
               repossess the Premises by forcible entry and detainer suit, by
               taking peaceful possession or otherwise, without terminating this
               Lease. If Landlord terminates Tenant's right of possession
               without terminating this Lease, Landlord shall take reasonable
               measures to the extent required by law, to relet the same for the
               account of Tenant, for such rent and upon such terms as shall be
               reasonably satisfactory to Landlord. Reasonable measures


                                       31

<PAGE>

               shall not obligate Landlord to show the Premises before showing
               other space in the Building to a prospective tenant. For the
               purpose of such reletting, Landlord is authorized to decorate,
               repair, remodel or alter the Premises and to relet the Premises
               at such rental rate (which may be higher than the rental rate
               then applicable under this Lease), as Landlord reasonably
               determines to be necessary to maximize the effective rent on
               reletting. If Landlord shall fail to relet the Premises, Tenant
               shall pay to Landlord as damages the amount of the Rent reserved
               in this Lease for the balance of the Term as due hereunder. If
               the Premises are relet and a sufficient sum shall not be realized
               from such reletting after paying all of the costs and expenses of
               all decoration, repairs, remodeling, alterations, installations
               and additions and the expenses of such reletting (including all
               allowances, abatements and other tenant concessions required
               under then-existing market conditions), to satisfy the Rent
               provided for in this Lease, Tenant shall satisfy and pay the same
               upon demand therefor from time to time. Tenant shall not be
               entitled to any rents received by Landlord in excess of the Rent
               provided for in this Lease. Tenant agrees that Landlord may file
               suit to recover any sums falling due under the terms of this
               Section 22 from time to time and that no suit or recovery of any
               portion due Landlord hereunder shall be any defense to any
               subsequent action brought for any amount not theretofore reduced
               to judgment in favor of Landlord.

     (c)  JURY TRIAL WAIVER. TENANT HEREBY WAIVES ITS RIGHTS TO A TRIAL BY JURY
          IN ANY ACTION OR PROCEEDING BASED UPON OR RELATED TO THE SUBJECT
          MATTER OF THIS LEASE AND THE BUSINESS RELATIONSHIP THAT IS BEING
          ESTABLISHED. THIS WAIVER IS KNOWINGLY, INTENTIONALLY AND VOLUNTARILY
          MADE BY TENANT AND TENANT ACKNOWLEDGES NEITHER LANDLORD NOR ANY PERSON
          ACTING ON BEHALF OF LANDLORD HAS MADE ANY REPRESENTATIONS OF FACT TO
          INCLUDE THIS WAIVER OF TRIAL BY JURY OR HAS TAKEN ANY ACTIONS WHICH IN
          ANY WAY MODIFY OR NULLIFY ITS EFFECT. TENANT ACKNOWLEDGES THAT THIS
          WAIVER IS A MATERIAL INDUCEMENT TO ENTER INTO THIS LEASE AND THAT
          LANDLORD HAS ALREADY RELIED ON THIS WAIVER IN ENTERING INTO THIS LEASE
          AND THAT LANDLORD WILL CONTINUE TO RELY ON THIS WAIVER IN ITS FUTURE
          DEALINGS WITH TENANT. TENANT FURTHER ACKNOWLEDGES THAT IT HAS BEEN
          REPRESENTED (OR HAS HAD THE OPPORTUNITY TO BE REPRESENTED) IN THE
          SIGNING OF THIS LEASE AND IN THE MAKING OF THIS WAIVER BY INDEPENDENT
          LEGAL COUNSEL.

23.  EXPENSES OF ENFORCEMENT

     The prevailing party shall be entitled to receive from the other party
     hereto upon demand all reasonable costs, charges and expenses including the
     reasonable fees and out-of-pocket expenses of counsel (including in-house
     attorneys), agents and others retained by the prevailing party incurred in
     enforcing the obligations hereunder against the other party hereto.


                                       32

<PAGE>

24.  COVENANT OF QUIET ENJOYMENT

     Landlord covenants that Tenant, on paying the Rent, charges for services
     and other payments herein reserved and on keeping, observing and performing
     all the other terms, covenants, conditions, provisions and agreements
     herein contained on the part of Tenant to be kept, observed and performed,
     shall, during the Term, peaceably and quietly have, hold and enjoy the
     Premises subject to the terms, covenants, conditions, provisions and
     agreements hereof.

25.  REAL ESTATE BROKER

     Each party represents that it has dealt with (and only with) the Broker(s)
     specified in Item 8 of the Schedule as broker in connection with this
     Lease, and that insofar as such party knows, no other brokers negotiated
     this Lease or are entitled to any commissions in connection therewith. Each
     party agrees to indemnify, defend and hold the other and its employees,
     agents, their officers and partners, harmless from and against any claims
     resulting from a breach of the foregoing representation.

26.  MISCELLANEOUS

     (a)  RIGHTS CUMULATIVE. All rights and remedies of Landlord under this
          Lease shall be cumulative and none shall exclude any other rights and
          remedies allowed by law.

     (b)  INTEREST. All payments becoming due under this Lease and remaining
          unpaid after the expiration of any applicable notice and cure period
          shall bear interest from the date first due until the date paid at the
          greater of (i) twelve percent (12%) per annum or (ii) four percent
          (4%) per annum above the Prime Rate (as such term is defined in
          Section 3.(a)(iii) D. hereof) (but in no event at a rate which is more
          than the highest rate which is at the time lawful in the State of
          Illinois).

     (c)  TERMS. The necessary grammatical changes required to make the
          provisions hereof apply either to corporations or partnerships or
          individuals, men or women, as the case may require, shall in all cases
          be assumed as though in each case fully expressed. Tenant acknowledges
          that "Rentable Area" as used in this Lease includes a portion of the
          common and service areas of the Building. Landlord makes no
          representation or warranty as to the rentable or usable square footage
          of the Premises, and Tenant agrees that Landlord's determination of
          the Rentable Area of the Premises and Tenant's Proportionate Share
          shall be conclusive and binding upon Tenant absent manifest error.

     (d)  BINDING EFFECT. Each of the provisions of this Lease shall extend to
          and shall, as the case may require, bind or inure to the benefit not
          only of Landlord and of Tenant, but also of their respective
          successors or assigns, provided this clause shall not permit any
          assignment by Tenant contrary to the provisions of Section 15 hereof.

     (e)  LEASE CONTAINS ALL TERMS. All of the representations and obligations
          of Landlord and Tenant are contained herein and in the Exhibits
          attached hereto, and


                                       33

<PAGE>

          no modification, waiver or amendment of this Lease or of any of its
          conditions or provisions shall be binding upon the Landlord or Tenant
          unless in writing signed by such party or by a duly authorized agent
          of such party empowered by a written authority signed by such party.

     (f)  DELIVERY FOR EXAMINATION. Submission of the Lease for examination
          shall not bind Landlord in any manner, and no Lease or obligations of
          the Landlord shall arise until this instrument is signed by both
          Landlord and Tenant and delivery is made to each.

     (g)  NO AIR RIGHTS. No rights to any view or to light or air over any
          property, whether belonging to Landlord or any other person, are
          granted to Tenant by this Lease.

     (h)  MODIFICATION OF LEASE. If any lender requires, as a condition to its
          lending funds the repayment of which is to be secured by a mortgage or
          trust deed on the Land and Building or either, that certain
          modifications be made to this Lease, which modifications will not
          require Tenant to pay any additional amounts or otherwise change
          materially the rights or obligations of Tenant hereunder, Tenant
          shall, upon Landlord's request, execute appropriate instruments
          effecting such modifications.

     (i)  TRANSFER OF LANDLORD'S INTEREST. Tenant agrees that Landlord has the
          right to transfer its interest in the Land and Building and in this
          Lease. If such a transfer occurs, Landlord shall automatically be
          released from all liability under this Lease arising after the date of
          such transfer and Tenant agrees to look solely to such transferee for
          the performance of Landlord's obligations hereunder arising after the
          date of such transfer. Tenant further acknowledges that the Landlord
          may assign its interest in this Lease to a mortgage lender as
          additional security and agrees that such an assignment shall not
          release Landlord from its obligations hereunder and that Tenant shall
          continue to look to Landlord for the performance of its obligations
          hereunder.

     (j)  LANDLORD'S TITLE. Nothing herein contained shall empower Tenant to
          commit or engage in any act which can, shall or may encumber the
          estate of Landlord.

     (k)  PROHIBITION AGAINST RECORDING. Neither this Lease, nor the
          Subordination, Non-Disturbance and Attornment Agreement, nor any
          memorandum, affidavit or other writing with respect thereto, shall be
          recorded by Tenant or by anyone acting through, under or on behalf of
          Tenant, and the recording thereof in violation of this provision shall
          make this Lease null and void at Landlord's election.

     (l)  CAPTIONS. The captions of Sections, Subsections, Paragraphs and
          Subparagraphs are for convenience only and shall not be deemed to
          limit, construe, affect or alter the meaning of such Sections,
          Subsections, Paragraphs or Subparagraphs.


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<PAGE>

     (m)  COVENANTS AND CONDITIONS. All of the covenants of Tenant hereunder
          shall be deemed and construed to be "conditions," if Landlord so
          elects, as well as "covenants" as though the words specifically
          expressing or importing covenants and conditions were used in each
          separate instance.

     (n)  ONLY LANDLORD/TENANT RELATIONSHIP. Nothing contained in this Lease
          shall be deemed or construed by the parties hereto or by any third
          party to create the relationship of principal and agent, partnership,
          joint venturer or any association between Landlord and Tenant, it
          being expressly understood and agreed that neither the method of
          computation of Rent nor any act of the parties hereto shall be deemed
          to create any relationship between Landlord and Tenant other than the
          relationship of landlord and tenant.

     (o)  APPLICATION OF PAYMENTS. Landlord shall have the right to apply
          payments received from Tenant pursuant to this Lease (regardless of
          Tenant's designation of such payments) to satisfy any obligations of
          Tenant hereunder, in such order and amounts, as Landlord in its sole
          discretion, may elect.

     (p)  DEFINITION OF LANDLORD. All indemnities of Tenant contained herein
          which inure to the benefit of Landlord shall be construed to also
          inure to the benefit of (i) Landlord's beneficiaries if Landlord is a
          trust, (ii) Landlord's partners if Landlord is a partnership, (iii)
          Landlord's shareholders, officers and directors if Landlord is a
          corporation, (iv) any current or future mortgagees of the Land and/or
          Building, (v) the successors and assigns of any of the foregoing, and
          (vi) the respective beneficiaries, members, shareholders, directors,
          officers, partners, agents and employees, agents, managers, affiliates
          and employees of any persons mentioned in clauses (i) through (v)
          above.

     (q)  TIME OF ESSENCE. Time is of the essence of this Lease and each of its
          provisions.

     (r)  GOVERNING LAW. Interpretation of this Lease shall be governed by the
          laws of the State of Illinois.

     (s)  PARTIAL INVALIDITY. If any term, provision or condition contained in
          this Lease shall, to any extent, be invalid or unenforceable, the
          remainder of this Lease (or the application of such term, provision or
          condition to persons or circumstances other than those in respect to
          which it is invalid or unenforceable) shall not be affected thereby,
          and each and every other term, provision and condition of this Lease
          shall be valid and enforceable to the fullest extent possible
          permitted by law.

     (t)  SUBSTITUTION OF OTHER PREMISES. Landlord may substitute for a portion
          of the Premises other premises in the Building (herein referred to as
          the "New Premises") provided that: (i) the New Premises shall have
          approximately the same Rentable Area as that portion of the Premises
          being relocated; (ii) the New Premises shall be usable for Tenant's
          purpose, and (iii) the New Premises are located on the tenth (10th)
          floor in the Building contiguous to Tenant's existing Premises.
          Landlord shall improve the New Premises, at its expense, to
          substantially the same condition as that portion of the Premises being
          relocated


                                       35

<PAGE>

          and pay all reasonable costs incurred by Tenant in relocating to the
          New Premises.

27.  NOTICES

     (a)  All notices to be given under this Lease shall be in writing and
          delivered either (i) personally upon an officer of Landlord or Tenant,
          as the case may be, or (ii) by depositing such notice in the United
          States mail, certified or registered mail with return receipt
          requested, postage prepaid, or (iii) via reputable overnight air
          courier service (such as Federal Express or Airborne) and in every
          case addressed as set forth in the Schedule or if no address for
          Tenant is inserted in the Schedule, addressed to Tenant at Tenant's
          present address, and, after occupancy of the Premises by Tenant, to
          Tenant at 233 South Wacker Drive, Chicago, Illinois 60606.

     (b)  Notice via personal service shall be deemed to have been given when
          actually delivered. Notice given by certified or registered mail shall
          be deemed to have been given on the second business day after the date
          that the notice is deposited into the mail postage prepaid. Notice
          given via air courier shall be deemed given one (1) business day after
          it is accepted by said courier for next day delivery.

     (c)  Either Landlord or Tenant may change the location at which it receives
          notices to another location within the United States of America upon
          not less than ten (10) days notice to the other pursuant to this
          Section 27.

28.  LIMITATION OF LIABILITY

     Tenant, and any person claiming an interest in the Premises through or
     under Tenant, each agree to look solely to the interests of Landlord,
     Beneficial Fee Owner and Land Trustee from time to time in the Land and
     Building, and no judgments against such persons may be satisfied out of any
     other assets. In no event shall Landlord, Beneficial Fee Owner or Land
     Trustee (or any of their respective officers, directors, agents, advisors,
     managers, shareholders, partners, beneficiaries, affiliates or successors
     and assigns) ever have any personal liability for any covenant, agreement,
     obligation, warranty, representation, indemnity or undertaking under this
     Lease or otherwise or be answerable or liable in any equitable, judicial or
     administrative proceeding or order.

29.  RIGHT OF FIRST OFFER

     If at any time prior to the last twelve (12) months of the Term, any space
     adjacent to the Premises becomes available for leasing to tenants on the
     ninth (9th) (but only if Tenant is then occupying space on the 9th floor)
     or tenth (10th) floors of the Building, and if Tenant is not then in
     Default hereunder, then Landlord shall not lease such space to any party
     without first giving Tenant (i) notice of the availability of such space
     which shall include a description of the space, the proposed term and
     rental rate (including escalations, if any), abatements and allowances, if
     any, and other economic concessions that Landlord believes that it would
     agree to with respect to such space (the "Offered Terms") and (ii) ten (10)
     days after the date of such notice in which to commit in writing to lease
     such space on the Offered Terms for the remainder of Term, taking into
     account any


                                       36

<PAGE>

     modifications in such Offered Terms required by the fact that the remaining
     Term may be longer or shorter than that proposed by Landlord, and otherwise
     on the terms, covenants and conditions contained in this Lease. If Tenant
     fails, refuses or is otherwise unable to commit to such a lease within the
     ten (10) day period, Landlord shall have the right to lease the space to
     any third party or parties on such terms as are acceptable to Landlord,
     subject to Tenant's Expansion Option(s) hereunder, if any.

30.  TENANT'S OPTION TO RENEW

     The Tenant is hereby granted one (1) five (5) year option to renew the
     Lease ("Renewal Option"). If the Tenant desires to exercise the Renewal
     Option, it shall so notify the Landlord, in writing, not later than the
     first day of the twelfth (12th) month prior to the then current expiration
     date of the Term. Such notice shall only be effective if delivered at a
     time when the Tenant is not in Default hereunder or otherwise in default in
     the performance of any of its obligations under the terms and provisions of
     this Lease. Within thirty (30) days following its receipt of Tenant's
     notice of its desire to exercise the Renewal Option, given at the time and
     in the manner provided above, Landlord shall prepare and transmit to Tenant
     an appropriate amendment to this Lease extending the Term for five (5)
     years ("Extended Term") and specifying (i) the Base Rent for such
     extension, which shall be the base rental rate then being offered and
     accepted by Landlord to other tenants of comparable size and location
     renewing leases in the Building, as reasonably determined by Landlord and
     evidenced by recent transactions which shall be disclosed to Tenant
     ("Market Rent") and (ii) that all other terms and conditions during the
     Extended Term are the same as those during the Term, except for any
     expansion rights, reduction rights or limitations on taxes and operating
     expenses. In the event the Tenant shall fail for any reason to execute and
     deliver the lease amendment within twenty (20) business days of Tenant's
     receipt of the same, Tenant's purported exercise of its Renewal Option
     shall be of no force or effect and the Renewal Option shall become null and
     void. In the event Tenant shall be in Default hereunder at the commencement
     of the Extended Term then, at Landlord's option, Tenant's purported
     exercise of its Renewal Option shall be of no force or effect and the
     Renewal Option shall become null and void.

31.  SPECIAL IMPROVEMENTS

     (a)  USE OF BUILDING STAIRWELLS. Tenant shall have the right to use the
          existing Building stairwells located at the northeast, southeast and
          southwest corners of the Building for access between the ninth and
          tenth floors in the Premises, subject to all applicable governmental
          laws and regulations which may, at any time, prohibit or restrict such
          usage. Tenant, at Tenant's sole cost and expense, prior to such use,
          shall install a card key or similar access system reasonably
          acceptable to Landlord on the stairwell side of each door leading into
          the Premises from such stairwell. Landlord shall not be responsible
          for any maintenance, decorating or other improvement of such
          stairwell. Landlord reserves the right to establish such reasonable
          rules and regulations as may be necessary with respect to Tenant's use
          thereof.

     (b)  SIGNAGE. Landlord approves Tenant's installation of a sign at both the
          floor elevator lobby and the entrance to Tenant's space on each floor
          of the Premises identifying


                                       37

<PAGE>

          Tenant. All such signs shall be of a size and quality consistent with
          similar signs elsewhere in the Building.

     (c)  ROOFTOP COMMUNICATIONS EQUIPMENT. Tenant shall have the right to
          install a microwave antenna on the roof of the Building provided that
          such antenna is used solely for Tenant's business purposes and
          provided further that such installation meets all requirements
          established by law and by Landlord with respect to other communication
          activities taking place on the roof. Tenant acknowledges that major
          communications operations are conducted on the roof of the Building
          and that the rights of such users shall be superior to those of
          Tenant. There shall be no monthly rental for Tenant's installation and
          use of such a microwave antenna. Tenant shall reimburse Landlord for
          all out-of-pocket costs incurred in obtaining access to the Building
          communications shaft, installing any necessary cabling and the rooftop
          installation. All such installation shall be done by contractors
          satisfactory to Landlord at times and under conditions specified by
          Landlord.

     (d)  METROPOLITAN CLUB. Landlord shall cause the initiation fee at the
          Metropolitan Club to be waived for twenty (20) of Tenant's employees.
          In addition the basic monthly membership fee for the first eighteen
          (18) months of the Term for such twenty employees shall also be
          waived. Such employees may upgrade their membership to include a
          health club membership for $25 per month during such eighteen month
          period. After such eighteen month period all fees shall be paid by
          Tenant or its employees.

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

                                        LANDLORD:

                                        233 S WACKER LLC,
                                        A DELAWARE LIMITED LIABILITY COMPANY


                                        By: /s/ John M. Houston
                                            ------------------------------------
                                        Its: Authorized Member


                                        TENANT:

                                        SPSS, INC.
                                        A DELAWARE CORPORATION


                                        By: /s/ Raymond H. Panza
                                            ------------------------------------
                                        Its: Executive Vice President,
                                             Corporate Operations and Chief
                                             Financial Officer


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