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                                                                    Exhibit 10.3

                          AMENDED AND RESTATED LEASE
                          --------------------------


     THIS AMENDED AND RESTATED LEASE (the "Lease") is made as of the 15th day of
December, 1997  between 35 W. Wacker Venture, L.L.C., a Delaware limited
liability company ("Landlord"), and LEO BURNETT COMPANY, INC., a Delaware
corporation ("Tenant");


                                  WITNESSETH
                                  ----------

     WHEREAS, Landlord's predecessor in interest, Harris Trust and Savings Bank,
not individually but solely as Trustee under Trust Agreement dated September 24,
1986 and known as Trust No. 43770 ("Trustee"), and Tenant entered into: (i) a
certain Lease dated as of January 22, 1987; (ii) a certain First Amendment to
Lease dated as of February 13, 1991, and (iii) a certain Second Amendment to
Lease dated as of January 8, 1993 (said Lease, as amended by the First Amendment
to Lease and Second Amendment to Lease is called the "Existing Lease"), pursuant
to which Trustee leased to Tenant and Tenant leased from Trustee certain
Premises (hereinafter defined) currently occupied by Tenant in the Land and
Building (each hereinafter defined) commonly known as 35 W. Wacker Drive,
Chicago, Illinois;

     WHEREAS, pursuant to a certain Agreement Regarding Acquisition of Limited
Liability Company Interest dated as of October 3, 1997 (the "Contribution
Agreement"), Tenant has agreed to cause Trustee to convey unto Landlord, all of
Trustee's right, title and interest in and to the Land and Building (the
"Contribution");

     WHEREAS, the Contribution Agreement provides for the termination of the
Existing Lease upon the closing of the Contribution, and the entering into by
Landlord and Tenant of this Lease pursuant to which Landlord will lease to
Tenant, and Tenant will lease from Landlord, the Premises for a term beginning
on the closing date of the Contribution and ending on the date(s) set forth
herein;

     NOW, THEREFORE, in consideration of these premises and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties agree as follows:

     1.   TERMINATION OF LEASE.  The Existing Lease shall terminate as of 11:59
          --------------------
p.m. on December 14, 1997 (the "Existing Lease Termination Date"), which is the
day immediately preceding the Commencement Date (hereinafter defined) of this
Lease, as if such Existing Lease Termination Date were set forth in the Existing
Lease as the expiration date of the term of the Existing Lease; except that
Tenant and Landlord shall remain liable for all obligations of such party
accruing under the Existing Lease prior to such Existing Lease Termination Date.

     2.   LEASING AGREEMENT. Landlord hereby leases to Tenant, and Tenant hereby
          -----------------
leases from Landlord, the premises described in Paragraph 2.A. of this Lease
(the "Premises") in the building commonly known as 35 West Wacker Drive,
Chicago, Illinois (the "Building") located on the land, legally described in
Exhibit A hereto, on the west one half of the block bounded by State Street,
Wacker Drive, Dearborn Street and Lake Street, all in the City of Chicago, Cook
County, Illinois  (together with all present and future easements and other
rights appurtenant thereto, the "Land"), subject to the covenants, terms,
provisions and conditions of this Lease.  The Building is
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comprised of a fifty (50) story office tower (the "Office Tower") and a three
(3) story retail bustle (the "Retail Space"). Tenant accepts the Premises in its
"as is" condition as of the date hereof. During the Term of this Lease, Tenant
shall have the right to use the one Building docking office (and adjoining
storage area) on lower Wacker Drive used by Tenant as of the date hereof for the
continued use of Tenant's loading dock personnel in the same manner as used by
Tenant as of the date hereof for shipping and receiving of materials. No
agreement of Landlord to alter, remodel, decorate, clean or improve the Premises
or Building (or to provide Tenant with any credit or allowance for the same),
and no representation regarding the condition of the Premises or Building, have
been made by or on behalf of Landlord or relied upon by Tenant, except as may be
expressly stated herein.

          Except as otherwise provided herein, Landlord specifically excepts and
reserves to itself the use of any roof decks, the exterior portions of the
Premises, and such areas within the Premises required for installation of
utility lines and other installations required to service other occupants of the
Building and to maintain and repair same, and no rights are conferred upon
Tenant, and Landlord specifically excepts and reserves to itself, unless
otherwise specifically provided, all rights to the land and improvements below
the lowest floor level of the Premises, to the improvements and air rights above
the Premises and to the land and improvements located outside the demising walls
of the Premises.

          A.   The "Premises" means and includes the Office Tower Premises and
the Retail Space Premises (both, as hereinafter defined). The "Office Tower
Premises" means and includes: (i) floors two through twenty-nine, inclusive, in
the Office Tower which the parties hereto acknowledge and agree contain 608,656
RSF; (ii) Suite 3401 in the Office Tower which the parties hereto acknowledge
and agree contains 25,000 RSF; and (iii) Suite 3740 in the Office Tower, which
the parties hereto acknowledge and agree contains 1,278 RSF. The "Retail Space
Premises" means and includes Suite R-9 in the Retail Space, which the parties
hereto acknowledge and agree contains 8,889 RSF.

          B.   "RSF" shall mean, as the context requires, one square foot or a
number of square feet of Rentable Area in any given space.

          C.   "Rentable Area" shall be computed by measuring to the inside
finished surface of the dominant portion (50% or more of the vertical floor-to-
ceiling dimension) of the permanent outer building wall (including windows or
glass panels; if the windows are thermal pane windows, the inside finished
surface shall be deemed to be the center line of the air space between such
thermal panes) without deduction for any columns or projections necessary to the
Building and shall include all areas within such inside finished surface other
than public stairs (stairs shall be deemed public if they constitute part of the
Building's public stair system even if used by Tenant for access between floors
of the Premises to the extent permitted by law and barred to other tenants
except in cases of emergency), interior balconies, if any, elevator shafts,
flues, stacks, pipe shafts and other major vertical penetrations of the floor.

Rentable Area shall include:

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          (1)  With respect to each single tenancy floor, toilets, air
     conditioning rooms, fan rooms, janitor closets, lobbies, elevator lobbies,
     electrical closets and telephone and other telecommunication closets within
     and serving only such floor (or only floors occupied by the same tenant);
     and

          (2)  With respect to each multiple tenancy floor, for each particular
     premises on that floor, its share of the areas described in the preceding
     clause (1), together with the particular premises' share of all public
     corridors and other public areas on such floor, as they may be adjusted
     from time to time.  The tenant spaces on a multiple tenancy floor shall
     share 100% of the Rentable Area of that full floor.  The share of each
     tenant's space shall be based upon the usable area contained in that
     tenant's space (which shall be measured to the center of partitions that
     separate such space from other tenant spaces or public areas) compared to
     the total usable area on that full floor.

          (3)  With respect to each single or multiple tenancy floor, such
     floor's proportionate share (based on such floor's Rentable Area without
     such added factor compared to the Building's Rentable Area without such
     added factor) of the public lobby area in the Building; provided, however,
     that, as of the Commencement Date, the ratio of Tenant's Rentable Area with
     such added factor to Tenant's usable area (such usable area to be measured
     on the basis of standards established by BOMA) shall not exceed 1.12 to
     1.00.

          The parties hereto acknowledge and agree that, as of the date hereof:
(i) the Rentable Area of the Building contains 1,117,978 RSF with the Office
Tower containing 1,075,876 RSF and the Retail Space containing 42,102 RSF; and
(ii) the aggregate Rentable Area of the Premises contains 643,823 RSF.  Landlord
shall not increase Tenant's Proportionate Share Taxes - Office Tower, Tenant's
Proportionate Share Taxes - Retail Space, Tenant's Proportionate Share Operating
Expenses - Office Tower or Tenant's Proportionate Share Operating Expenses -
Retail Space (all, as hereinafter defined) except for additions to the RSF of
the Premises due to expansions of the Premises by Tenant pursuant to Paragraphs
30 and 32 hereof.  If the Rentable Area of either the Premises or the Building
(or any above described  portion thereof) changes in any Calendar Year during
the Term of this Lease, or any renewal thereof, such Rentable Area shall be
recomputed as aforesaid by Architect (as hereinafter defined)  and all
applicable adjustments hereunder shall be made as of the date of each such
change.  In the event of any dispute over Rentable Areas, Tenant shall make
payments based on the Rentable Areas determined by Landlord until resolution of
such dispute at which time any necessary adjustments shall be made and any
amounts due to Landlord or Tenant as a result shall be paid within thirty (30)
days after demand together with interest on such adjusted amount at 2% over the
Prime Rate.

     3.   TERM. The term of this Lease (the "Term") shall begin on December 15,
          ----
1997 (the "Commencement Date").  Unless sooner terminated as provided herein,
the Term shall end with the last day of the one hundred eightieth  (180th) full
calendar month subsequent to the Commencement Date (for example, December 31,
2012, if the Commencement Date were to be December 18, 1997), as such date may
be extended by the exercise of any one or more of the options conferred upon

                                      -3-
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Tenant under this Lease (the "Termination Date"). Notwithstanding the foregoing,
the Termination Date for Suite 3401 of the Premises shall be December 31, 2004.

     4.   BASE RENT.  Tenant shall pay to Landlord or Landlord's agent at the
          ---------
office of Landlord's agent at 35 W. Wacker Drive, Suite 3860, Chicago, Illinois
60606, or at such other place as Landlord may from time to time designate in
writing, in coin or currency which, at the time of payment, is legal tender for
private or public debts in the United States of America, "Base Rent" at annual
rate which is equal to the number of RSF within the Premises (excluding,
however, the 1,278 RSF of Suite 3740, for which Base Rent shall at no time
accrue or be payable during the Term of this Lease or any Extension Term) times
$14.55, net of Operating Expenses and Taxes.  Such annual rate shall be paid in
monthly installments of one-twelfth of the then-current annual rate in advance
on or before the first day of each and every month during the Term, without any
set-off, abatement, counterclaim or deduction whatsoever, except as otherwise
provided herein.  If the Term commences other than on the first day of a month,
the Base Rent for such month shall be prorated.  The prorated Base Rent for the
portion of the month in which the Term commences shall be paid on the first day
of the Term.  The Base Rent for the Initial Space and any other space added to
the Premises pursuant to Paragraph 30 hereof, shall be increased on each
anniversary of the Commencement Date by multiplying the then applicable Base
Rent by the decimal equivalent of 2.5% (i.e. .025).  A schedule of Base Rent for
the Premises for the initial Term of this Lease is attached hereto as Exhibit B.

     5.   ADDITIONAL RENT.  In addition to paying the Base Rent specified in
          ---------------
Paragraph 4 hereof, Tenant shall pay as "Additional Rent" for the Term an amount
equal to "Tenant's Expense Participation Amount" determined from time to time
during the Term pursuant to this Paragraph 5. The Base Rent and the Additional
Rent are sometimes herein collectively referred to as the "Rent." Tenant's
obligation to pay rent is an independent covenant and is a separate obligation,
except as otherwise set forth herein.  Except as otherwise provided in this
Paragraph 5, all amounts due under this Paragraph 5 as Additional Rent shall be
payable for the same periods and to the same party and at the same place as the
Base Rent.  Without limitation on other obligations of Tenant which shall
survive the expiration of the Term, the obligations of Tenant to pay the
Additional Rent provided for in this Paragraph 5 with respect to periods during
the Term shall survive the expiration of the Term.  For any partial Calendar
Year, Tenant shall be obligated to pay only a pro rata share of the Additional
Rent, based on the number of the days of the Term falling within such Calendar
Year.

          A.   Definitions.  As used in this Paragraph 5, the terms:
               -----------

          (1)  "Calendar Year" shall mean each calendar year in which any part
     of the Term falls.

          (2)  "Tenant's Proportionate Share" at any time during the Term shall
     mean the percentage calculated by dividing the number of RSF contained in
     the Premises by the number of RSF contained in the Building.

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          (3)  "Tenant's Proportionate Share Taxes - Office Tower" at any time
     during the Term shall mean the percentage calculated by dividing the number
     of RSF contained in the Office Tower Premises by the number of RSF
     contained in the Office Tower.

          (4)  "Tenant's Proportionate Share Taxes - Retail Space" at any time
     during the Term shall mean the percentage calculated by dividing the number
     of RSF contained in the Retail Space Premises by the number of RSF
     contained in the Retail Space.

          (5)  "Tenant's Proportionate Share Operating Expenses - Office Tower"
     at any time during the Term shall mean the percentage calculated by
     dividing the number of RSF contained in the Office Tower Premises by
     1,065,926 RSF.

          (6)  "Tenant's Proportionate Share Operating Expenses - Retail Space"
     at any time during the Term shall mean the percentage calculated by
     dividing the number of RSF contained in the Retail Space Premises by 26,344
     RSF.

          (7)  "Taxes" shall mean in any Calendar Year all real estate taxes and
     assessments, special or otherwise, sewer rents, rates, charges, water taxes
     or transit taxes, upon or with respect to the Land and/or Building and ad
     valorem taxes for any personal property used in connection therewith, which
     are paid or payable during such Calendar Year (but shall not include any
     such taxes or assessments which are a lien but are not payable during such
     Calendar Year).  Should the State of Illinois, or any political subdivision
     thereof, or any other governmental authority having jurisdiction over the
     Land and/or the Building, (a) impose or increase a tax, assessment, charge
     or fee which Landlord shall be required to pay, by way of substitution in
     whole or in part for such real estate taxes and ad valorem personal
     property taxes or an increase therein, or (b) impose or increase an income
     or franchise tax or a tax on rents in substitution in whole or in part for
     a tax levied against the Land and/or the Building and/or the personal
     property used in connection with the Land or Building, or an increase
     therein, all such taxes, assessments, fees or charges (hereinafter defined
     as "in lieu of taxes") shall, to the extent they do constitute such a
     substitution, be deemed to constitute Taxes hereunder if paid or payable
     during a Calendar Year.  Taxes shall also include, in the year paid, all
     fees and costs reasonably incurred by Landlord in seeking to obtain a
     reduction of, or a limit on the increase in, any Taxes (and Landlord shall
     seek to obtain such a reduction of or a limit on the increase in Taxes each
     and every year), but only to the extent of any reduction or limitation so
     obtained.  Except as hereinafter provided with regard to "in lieu of
     taxes," Taxes shall not include any inheritance, estate, succession,
     transfer, gift, franchise, net income or capital stock tax, or any
     penalties for the late payment by Landlord of any Taxes.

          "In lieu of taxes" shall also mean leasehold taxes imposed upon the
     Landlord in connection with the leasing and operation of the Building or
     the Land, except to the extent such taxes constitute income or other taxes
     imposed upon or measured by the general net income or profits of the
     Landlord.

                                      -5-
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          In the event that Landlord is required by federal, state or local
     statute or ordinance to collect taxes imposed upon Tenant in connection
     with this Lease, Tenant shall cooperate with Landlord in the collection and
     payment of same, shall execute and deliver such forms and other documents
     as shall be reasonably required to enable Landlord to collect and pay such
     taxes and shall remit to Landlord all required payments, including interest
     and penalties prior to the date said taxes are due and payable.  In the
     event that such taxes may be paid directly by Tenant, Tenant shall
     cooperate with Landlord in making any requests or applications to enable
     Tenant, rather than Landlord, to pay such tax, and Tenant shall pay such
     tax directly to the appropriate governmental authorities after the required
     approvals are obtained.

          (8)  "Operating Expenses" shall mean all expenses, costs and
     disbursements (other than Taxes) of every kind and nature paid or accrued
     (with any appropriate accounting adjustments if the manner of accounting
     for any item is changed during the Term) by Landlord in any Calendar Year
     in connection with the management, operation, leasing and repair of the
     Land and Building and personal property used solely in connection therewith
     (specifically including the provision of any of the future services
     described in Paragraph 7A(9)), except the following:

               (a)  Costs of alterations of any tenant's premises, including,
          but not limited to, preparing tenantable space for a tenant's initial
          occupancy or lease renewal or extension;

               (b)  Principal or interest payments on loans secured by mortgages
          or trust deeds on the Building and/or the Land (including any
          refinancings of the Building and/or the Land), or lease rentals paid
          or payable on any ground or underlying lease;

               (c)  Costs of capital improvements, except that Operating
          Expenses shall include: (i) the cost of any capital improvements
          completed after the Commencement Date which are not a part of the
          initial construction of the Building and which are reasonably
          estimated by Landlord to reduce Operating Expenses, provided (v) such
          cost must be evenly amortized by Landlord over the useful life of the
          capital improvement, with interest on the unamortized amount at the
          prime or base rate of interest announced from time to time by The
          First National Bank of Chicago, or another major national bank
          selected by Landlord if The First National Bank of Chicago shall not
          at any time be in existence or be announcing a prime or base rate
          ("Prime Rate"), (w) such amortized costs (including interest as
          aforesaid) shall only be included in Operating Expenses under this
          Lease for that portion of the useful life of the capital improvement
          which falls within the Term, (x) that portion of the annual amortized
          costs (including interest as aforesaid) to be included in Operating
          Expenses shall be the lesser of such annual costs or the projected
          annual reduction in Operating Expenses for that portion of the useful
          life of the capital improvement which falls within the Term, as
          reasonably estimated by Landlord and certified by a qualified engineer
          in detail by expense category prior to making such

                                      -6-
<PAGE>

          capital improvement, (y) all elements of such projection shall be
          completed in accordance with generally accepted accounting principles
          and practices in effect at the time the capital improvement is
          proposed to be made; and (z) a copy of such projection of the
          underlying calculations shall be furnished to Tenant prior to
          Landlord's including the cost of any such capital improvement in
          Operating Expenses; and (ii) provided that conditions (i)(v) and
          (i)(w) above are satisfied, the cost of any capital improvement made
          by Landlord to keep the Land or Building in compliance with all
          governmental rules and regulations enacted after the Commencement
          Date;

               (d)  All expenses for which Landlord has received any
          reimbursement to the extent of such reimbursement, other than indirect
          reimbursement by the payment by any tenant of base rent or its share
          of Operating Expenses;

               (e)  Attorneys' fees, costs and disbursements and other expenses
          incurred in connection with tenant leases, including, without
          limitation, negotiations with prospective tenants or disputes with any
          tenant but excluding any expenses incurred in the performance of any
          of Landlord's obligations under such tenant leases which are
          reimbursed by tenants' payment of Operating Expenses;

               (f)  Expenses for repairs or other work occasioned by a casualty,
          except that Operating Expenses shall include the deductible amount
          permitted in Paragraph 11.C.;

               (g)  Depreciation;

               (h)  Real estate brokers' commissions or compensation and other
          expenses (including, without limitation, architectural, space planning
          or engineering services) incurred in leasing or procuring tenants;

               (i)  The cost of any electric current furnished for lighting and
          equipment (other than for the operation of fan rooms, telephone
          closets and other elements of the Building's shared systems) located
          in the Premises or in premises occupied by any other tenant in the
          Building;

               (j)  The cost of correcting defects in the construction of the
          Building or in the Building equipment provided that this shall not
          exclude the cost of normal repair, maintenance and replacement
          expected with the construction materials and equipment installed in
          the Building in light of their specifications;

               (k)  The cost of any repair made by Landlord pursuant to or as a
          result of condemnation;

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<PAGE>

               (l)  The cost of installing, operating and maintaining any
          specialty facility, such as an observatory, broadcasting facilities,
          luncheon club, athletic or recreational club, cafeteria or dining
          facility;

               (m)  The cost of any repairs, alterations, additions, charges,
          replacements and other items not specifically referred to in this
          Paragraph 5 and which, under generally accepted accounting principles,
          are properly classified as capital expenditures;

               (n)  Any management or other fees and expenses paid to an agent
          which is related to Landlord or its beneficiary to the extent such
          fees are in excess of the customary amounts which would be paid in the
          absence of such relationship;

               (o)  Executive salaries or fringe benefits of personnel above the
          grade of Building Manager;

               (p)  Expenses incurred in connection with services or other
          benefits of a type which are not available generally to all office
          tenants of the Building;

               (q)  Any penalty charges incurred by Landlord due to the
          violation of any law, order or regulation of any authority;

               (r)  Any compensation paid to clerks, attendants or other persons
          in commercial concessions operated by Landlord;

               (s)  Advertising and promotional expenditures;

               (t)  Costs for sculptures, paintings and other objects of art
          located within the Building, except only for the costs of maintaining
          such objects in the public areas of the Building;

               (u)  Expenses incurred by Landlord, if any, in connection with
          the operation, cleaning, repair, safety, management, security,
          maintenance or other services of any kind provided to the portions of
          the Building which are leased for retail purposes, if retail tenants
          do not participate in paying such costs and expenses as a separate
          component of their rent. If the foregoing is the case, then the
          calculation of RSF in the Building shall exclude the retail space. If
          they do participate in paying for such costs and expenses, then only
          that portion of such costs and expenses that reflects a higher cost
          and expense due to greater usage by retail tenants shall be excluded
          from Operating Expenses;

               (v)  Expenses incurred by Landlord, if any, in connection with
          the operation of the parking garage in the Building;

                                      -8-
<PAGE>

               (w)  Any management fee in excess of 1.5% of the annual Gross
          Revenue (as hereinafter defined) of the Building;

               (x)  Costs of relocating tenants of the Building;

               (y)  Taxes;

               (z)  Interest or penalties for late payment for fuel, gas steam,
          electricity, water, sewer or other utilities; and

               (aa) Costs incurred in connection with a transfer or disposal of
          all or any part of the Building or Land or any interest therein or in
          Landlord or any entity comprising Landlord.

               (bb) Expenses incurred by Landlord in connection with night
          cleaning of the Retail Space, provided, however, that Tenant shall pay
          Landlord directly (as opposed to as an Operating Expense pass-thru)
          for Landlord's actual costs incurred in connection with the night
          cleaning of the Retail Space Premises.

          (9)  "Tenant's Expense Participation Amount" with respect to each
     Calendar Year, shall equal  the sum of:  (i) Tenant's Proportionate Share
     Taxes - Office Tower of the Taxes for the Office Tower for such Calendar
     Year,  (ii) Tenant's Proportionate Share Taxes -Retail Space of the Taxes
     for the Retail Space for such Calendar Year, (iii) Tenant's Proportionate
     Share Operating Expenses - Office Tower of Operating Expenses for the
     Office Tower for such Calendar Year, and (iv) Tenant's Proportionate Share
     Operating Expenses - Retail Space of Operating Expenses for the Retail
     Space for such Calendar Year, as such Proportionate Shares may be adjusted
     from time to time during such Calendar Year. Notwithstanding the foregoing,
     prior to calculating Tenant's Proportionate Share Operating Expenses -
     Office Tower for each Calendar Year, the total amount of Operating Expenses
     for the Office Tower for each Calendar Year shall be reduced by $50,000.00.

          (10) "Gross Revenue" as used herein shall mean the aggregate of all
     rents, income and receipts of every kind and description actually received
     by or for the account of Landlord in connection with or arising from the
     use, occupancy or operation of the Building, including, without limitation,
     (a) base or fixed rent, percentage and other amounts payable as rent, other
     charges, fees and payments received from tenants including, without
     limitation, operating expenses and real estate taxes payable by any tenant
     pursuant to any leases; and (b) proceeds of business interruption and rent
     loss insurance to the extent received by Landlord in lieu of the receipts
     described in (i) above; provided, however, that Gross Revenues shall not
     include: (i) any security deposits received until applied to rent; (ii) any
     income amount received which is considered an extraordinary financial item,
     or an amount not received in the ordinary course of business under any
     lease; (iii) any loan repayments by tenants for above standard tenant
     improvements (other than loan repayments, including principal and interest,
     made by Winston & Strawn pursuant to its lease for space in the

                                      -9-
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     Building); (iv) any net income collected in connection with the provision
     of any extra services by Landlord to a tenant; and (v) interest or other
     investment income.

          (11) If the Building is not 95% or more occupied during all or any
     portion of a Calendar Year then Landlord may elect to make an appropriate
     adjustment of the Operating Expenses that vary according to the occupancy
     level of the Building for such Calendar Year to determine the amount of
     such Operating Expenses that would have been paid or incurred had the
     Building been 95% occupied and the amount so determined shall be deemed to
     have been the amount of such Operating Expenses for such Calendar Year.

          B.   Payment of Additional Rent.  Landlord shall furnish Tenant, at
               --------------------------
least thirty (30) days prior to the commencement of each Calendar Year and from
time to time (but not more than twice) during each such Calendar Year, written
statements setting forth Landlord's then-current reasonable estimate of Tenant's
Expense Participation Amount for such Calendar Year. Tenant shall pay to
Landlord as Additional Rent on the first day of each month during each Calendar
Year, together with the payment of Base Rent, if any, an amount equal to one-
twelfth (1/12th) of Landlord's then-current reasonable estimate of Tenant's
Proportionate Share Operating Expenses -Office Tower of Operating Expenses for
the Office Tower for such Calendar Year and one-twelfth (1/12th) of Landlord's
then-current reasonable estimate of Tenant's Proportionate Share Operating
Expenses - Retail Space of Operating Expenses for the Retail Space for such
Calendar Year, plus any amounts that would have been paid for months prior to
the current month if Landlord's current estimate had been in effect during those
months. Tenant shall pay to Landlord not later than fifteen (15) days prior to
the date on which Taxes are required to be paid by Landlord, Tenant's
Proportionate Share Taxes - Office Tower of Taxes payable for the Office Tower
and Tenant's Proportionate Share Taxes - Retail Space of Taxes payable for the
Retail Space for each Calendar Year. Landlord shall provide Tenant with a copy
of the most recent Tax bills for the Office Tower and Retail Space and a
statement indicating Tenant's Proportionate Share Taxes - Office Tower of Taxes
for the Office Tower and Tenant's Proportionate Share Taxes - Retail Space of
Taxes for the Retail Space at least forty (40) days prior to the date such Taxes
are due. In addition to the foregoing, for the first twelve (12) months of the
Term, on the first day of each such month, Tenant shall pay to Landlord an
amount equal to the sum of (i) one-twenty fourth (1/24th) of Tenant's
Proportionate Share Taxes - Office Tower of Taxes for the Office Tower which
were paid for Calendar Year 1996 and (ii) one-twenty fourth (1/24th) of Tenant's
Proportionate Share Taxes -Retail Space of Taxes for the Retail Space which were
paid for Calendar Year 1996 (said sum, the "Tax Escrow"). Landlord shall place
the Tax Escrow in a separate account, invest such payments in reasonable and
liquid securities at the direction of Tenant and at Tenant's expense. Following
the final payment of Taxes payable for the Calendar Year 1997 and each
subsequent Calendar Year, Landlord shall notify Tenant of any increases in Taxes
from the prior Calendar Year and shall apply for Tenant's benefit any interest
earned on the amount held in the Tax Escrow during the prior Calendar Year, and
shall remit any excess interest to Tenant, or request Tenant to fund any
shortfall into the Tax Escrow, so that at all times the Tax Escrow shall contain
at lease one half of the amount of Tenant's Proportionate Share Taxes - Office
Tower of Taxes for the Office Tower and Tenant's Proportionate Share Taxes -
Retail Space of Taxes for the Retail Space paid for the then most recent
Calendar Year. Tenant shall deposit into the Tax Escrow any such shortfall
amount within thirty

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(30) days of Landlord's request. If Tenant fails to pay to Landlord Tenant's
Proportionate Share Taxes - Office Tower of Taxes for the Office Tower and
Tenant's Proportionate Share Taxes - Retail Space of Taxes for the Retail Space
for the Calendar Year when due as provided herein, Landlord may apply the Tax
Escrow to the amount of Taxes owed by Tenant. If any portion of the Tax Escrow
is applied to the payment of Taxes, Tenant shall, within thirty (30) days after
the written request of Landlord, pay to Landlord an amount sufficient to
replenish the Tax Escrow to its original level. On the Termination Date, Tenant
shall pay into the Tax Escrow an amount necessary to increase the Tax Escrow to
the amount of Tenant's Proportionate Share Taxes - Office Tower of Taxes for the
Office Tower and Tenant's Proportionate Share Taxes - Retail Space of Taxes for
the Retail Space for Taxes which have accrued in the Calendar Year in which the
Termination Date occurs through the Termination Date. Landlord shall use the Tax
Escrow for the payment of Tenant's share of Taxes for the final Calendar Year of
the Term and shall pay any excess remaining in the Tax Escrow (and any interest
earned thereon) to Tenant within thirty (30) days. If Tenant's share of Taxes
for the final Calendar Year of the Term exceeds the amount held in the Tax
Escrow, Tenant shall, within thirty (30) days after the written request of
Landlord, pay such excess to Landlord. Notwithstanding anything to the contrary
contained herein, Tenant shall pay Tenant's Proportionate Share Taxes - Office
Tower of 1997 Taxes for the Office Tower and Tenant's Proportionate Share
Taxes -Retail Space of 1997 Taxes for the Retail Space for the entire Calendar
Year 1997, regardless of when the Commencement Date of this Lease actually
occurs. Tenant also agrees that it shall remain responsible for Tenant's
Proportionate Share Taxes - Office Tower and Tenant's Proportionate Share
Taxes -Retail Space for any Contraction Space with respect to which Tenant has
exercised its option under Section 31 for the Calendar Year in which such
Contraction Space is vacated by Tenant through the applicable Contraction Date,
although payable in the subsequent Calendar Year.

          Landlord agrees to keep true and accurate records of all Operating
Expenses.  Prior to May 1 of each Calendar Year, Landlord shall submit to Tenant
a detailed statement certified by a certified public accountant (the "Operating
Statement") setting forth (A) the actual amount of Operating Expenses and Taxes
for the previous Calendar Year, (B) the amount of Tenant's Expense Participation
Amount on account of such previous Calendar Year and (C) the payments made by
Tenant on account thereof.  If the installments made on account of such previous
Calendar Year exceed Tenant's Expense Participation Amount due on account of
such Calendar Year, as shown on the Operating Statement, such excess shall be
credited by Landlord against the next succeeding installment(s) of Tenant's
Expense Participation Amount; provided if Tenant is not in default under this
Lease, Landlord shall at Tenant's request refund such excess to Tenant within
thirty (30) days of such request.  If, however, said installment(s) are less
than Tenant's Expense Participant Amount due on account of such Calendar Year,
as shown on the Operating Statement, then Tenant agrees to pay to Landlord the
amount necessary to make up any deficiency within thirty (30) days after the
delivery of the Operating Statement to Tenant.

          C.   Miscellaneous re Additional Rent.  If the date the Term commences
               --------------------------------
is not the first day of a Calendar Year, or if the date of expiration or
termination of this Lease is not the last day of a Calendar Year, the Tenant's
Expense Participation Amount shall be prorated based upon the number of days of
the applicable partial Calendar Year within the Term.

                                     -11-
<PAGE>

          Every Operating Statement given by Landlord pursuant to Paragraph 5.B.
shall be conclusive and binding upon Tenant unless (i) Tenant shall notify
Landlord that it disputes the correctness of the then current Operating
Statement or Operating Statements from the previous two (2) years, specifying
the particular respects in which the Operating Statement is claimed to be
incorrect, and (ii) if such dispute shall not have been settled by agreement, it
shall be settled by submission of such dispute to a national public accounting
firm acceptable to Landlord and Tenant, at the expense of Tenant, except as
hereinafter provided, for a final and binding determination. Pending the
determination of such dispute, Tenant shall within thirty (30) days after
receipt of such Operating Statement, pay any deficiency in Tenant's Expense
Participation Amount payment if due in accordance with the Operating Statement,
and such payment shall be without prejudice to Tenant's position.  If the
dispute shall be determined in Tenant's favor, Landlord shall, on demand, pay
Tenant the amount of Tenant's overpayment of Tenant's Expense Participation
Amount, if any, resulting from compliance with the Operating Statement.  If the
discrepancy was greater than two percent (2%) of the correct Operating
Statement, Landlord shall pay to Tenant interest on such overpayment at the rate
of two percent (2%) per annum over the Prime Rate.  Landlord agrees to grant
Tenant reasonable access to Landlord's books and records, during normal business
hours, at Landlord's office, for the purpose of verifying Operating Expenses
incurred by Landlord, and to make copies of any and all bills and vouchers
relating thereto, subject to reimbursement by Tenant for the cost of such
copies.

          In the event that a review of Landlord's books and records pursuant to
this Paragraph 5 reveals that Landlord has overstated its Operating Expenses for
the applicable Calendar Year by 3% or more of the actual Operating Expenses
incurred for such Calendar Year, Landlord shall also reimburse Tenant for the
reasonable expenses incurred by Tenant in conducting  such review of Landlord's
books and records and for the amounts paid to the public accounting firm.  In
the event that there is an error of less than 3% in Landlord's statement of the
Operating Expenses, then Tenant shall pay the cost of the public accounting
firm.

          Tenant shall pay, in addition to Tenant's Expense Participation
Amount, all actual and reasonable expenses, costs and disbursements incurred by
Landlord and not included in Operating Expenses and which solely are
attributable to the operation and maintenance of equipment installed in the
Premises at Tenant's request for the exclusive use of Tenant, and which is not
generally available to other tenants of the Building.

     6.   USE OF THE PREMISES.  The Premises may be used and occupied for any
          -------------------
lawful purpose consistent with the operation of a first-class office building in
Chicago, Illinois, provided that any such use and occupancy complies with all
applicable building and zoning laws, codes and ordinances and such use is not
dangerous to person or property, does not invalidate or increase Landlord's
insurance premiums, does not create a nuisance or unreasonably disturb any other
tenant of the Building and does not injure the reputation of the Building.
Tenant may, if Tenant so elects, install and operate vending machines for the
exclusive use of Tenant's employees and invitees to dispense hot and cold
beverages, ice cream, candy, food and cigarettes, provided that such machines
shall be maintained in a neat and sanitary condition and shall comply with all
applicable laws and

                                     -12-
<PAGE>

ordinances. In addition, Tenant may, if Tenant so elects, install, equip and
operate one or more cafeterias or dining rooms in the Premises and serve
alcoholic beverages therein for the exclusive use of Tenant's employees and
invitees, subject to compliance with all applicable codes and ordinances and
provided (a) Tenant has delivered to Landlord certificates evidencing
satisfactory insurance against any liability of Landlord arising from such
serving of alcoholic beverages in the Premises; and (b) Tenant has made all
appropriate utility modifications at its expense and subject to Landlord's
reasonable approval and implemented appropriate pest control measures.

          Subject to Landlord's reasonable approval, Tenant shall have the right
from time to time to the use of the Building lobby for Tenant sponsored
presentations (a "Presentation") for up to a total of ten (10) days during each
Calendar Year.  Tenant shall provide Landlord with at least fourteen (14) days
prior notice of a Presentation (the "Presentation Notice").  Landlord shall be
deemed to have approved a Presentation if Landlord does not object in writing to
Tenant within seven (7) days after receipt of a Presentation Notice.

     7.   SERVICES.
          --------

          A.   List of Services.  Landlord shall provide the following services
               ----------------
at all times during the Term, subject to the following:

          (1)  Heating, ventilating and air-conditioning on all business days in
     accordance with the performance condition standards set forth in Exhibit C
     hereto.  The term "business day" means Monday through Friday during the
     period from 8 a.m. to 6 p.m. and on Saturday during  the period from 8 a.m.
     to 1 p.m., legal holidays excluded.  The term "legal holiday" means New
     Year's Day, Memorial Day, the 4th of July, Labor Day, Thanksgiving Day and
     Christmas Day.  If Tenant shall require heating, ventilating or air
     conditioning service at any other time ("after-hours"), Landlord shall
     furnish such after-hours service upon advance notice from Tenant given
     prior to 5:00 p.m. on any business day (noon on Saturdays) and on the
     previous business day with respect to after-hours service on Sunday or any
     legal holiday. Tenant shall pay for such after-hours service at Landlord's
     reasonable actual cost (including overhead but not profit) of furnishing
     same.  In the event the after-hours service is requested and shared by
     other tenants on the same floor, Tenant's share of such costs shall be
     appropriately reduced.

          Use of the Premises, or any part thereof, in a manner exceeding the
     performance conditions (including occupancy and connected electrical load)
     specified in Exhibit C or rearrangement of partitioning which  interferes
     with normal operation of the heating, ventilation and air-conditioning in
     the Premises, may require change in the heating, ventilation and air-
     conditioning system servicing the Premises.  Such changes, so occasioned,
     shall be made if feasible by Landlord at Tenant's expense upon Landlord's
     or Tenant's request therefor.

          (2)  Subject to the Building performance standards specified in
     Exhibit C, sufficient electrical capacity to operate typewriters,
     calculating machines, photocopying

                                     -13-
<PAGE>

     machines, data processing equipment, personal computers, laptop computers,
     and other equipment and accessories customarily used by means of standard
     floor, ceiling or wall outlets within the Premises. If any electrical
     equipment requires air-conditioning in excess of Building standard, the
     same shall be installed at Tenant's expense and Tenant shall pay all
     operating costs relating thereto.

          If Tenant's requirements for electricity are in excess of those set
     forth in this clause (2) the Landlord reserves the right to require Tenant
     to pay the cost of installation, operation and maintenance of the conduit,
     wiring and other equipment necessary to supply electricity for such excess
     use requirements at the Tenant's expense by arrangement with Commonwealth
     Edison Company or another approved local utility.

          Tenant shall bear the responsibility of replacement of all lamps and
     tubes for lighting fixtures, which Tenant may purchase from its own
     suppliers and install by its own maintenance persons.  The brand and type
     of such lamps and tubes shall be reasonably approved by Landlord, such
     approval to be based solely upon Landlord's desire to maintain a
     substantially uniform color and intensity of the interior lighting in the
     Building.

          (3)  Adequate hot and cold City water from the regular Building
     outlets for drinking, lavatory and toilet purposes. The water pressure must
     be a minimum of 35 to 40 pounds per square inch and the hot water
     temperature must be 100. Tenant shall pay the cost of installation,
     maintenance and replacement of any additional water requirements and
     equipment for any kitchen purposes in connection with the permitted dining
     rooms or cafeterias.

          (4)  Janitorial services as specified in Exhibit D attached hereto and
     identified as "Janitorial Services."  Landlord will supply all necessary
     janitorial products in its performance of Janitorial Services.  Subject to
     Landlord's reasonable approval and for so long as it does not cause any
     problems or disputes with any unions representing other workers in the
     Building, Tenant may contract with its own janitor to provide supplementary
     janitorial services to the Premises.  Landlord shall have no liability
     whatsoever for any losses or damages resulting from the acts or omissions
     of Tenant's own janitor and Tenant hereby indemnifies and holds Landlord
     harmless from any such losses or damages.  In contracting with such
     janitor, Tenant will not knowingly take any action which will directly
     result in picketing of the Building or the concerted withholding of
     services by any employees of Landlord or Landlord's beneficiary and should
     any such action occur Tenant will take any reasonable steps available to
     bring such action to an end.

          (5)  Window washing for the inside and outside of windows in the
     Building's perimeter walls as may be situated in the Premises at intervals
     to be determined by Landlord, but not less than four times per year.

          (6)  Adequate automatic passenger elevator service available 24 hours
     a day, seven days a week.

                                     -14-
<PAGE>

          (7)  Freight elevator services subject to reasonable scheduling by
     Landlord and appropriate charges for night and weekend use.

          (8)  Building Directory for Tenant with one line for Tenant for every
     400 RSF in the Premises from time to time but not to exceed 1,500 lines.
     Landlord's design and placement of all Building Directories shall be
     subject to Tenant's reasonable approval.

          (9)  Landlord agrees to furnish such other services as are customarily
     furnished by landlords of other first-class office buildings in the City of
     Chicago, to the extent such service can be provided without additional
     capital improvements and provided the cost of such services can be included
     in the Operating Expenses.  Notwithstanding the foregoing, Landlord shall
     not decrease the level of quality of services provided to Tenant as of the
     date hereof.

          B.   Billing for Electricity.  Tenant shall pay for the use of all
               ------------------------
electrical service to the Premises.  Provided that Landlord can make
satisfactory arrangements with the utility company supplying electricity to the
Premises for separate metering and billing, Tenant shall be billed directly by
such utility company.  In the event that for any reason the Premises are
metered, but Tenant cannot be billed directly, Landlord shall forward each bill
received by it with respect to the Premises to Tenant and Tenant shall pay it
promptly in accordance with its terms.

          Landlord has advised Tenant that presently Commonwealth Edison (the
"Electric Service Provider") provides electricity service to the Building.
Notwithstanding the foregoing, if permitted by law, Landlord shall have the
right at any time and from time to time during the Term of this Lease to either
contract for electricity service from a different company or companies providing
electricity service (each such company, an "Alternate Service Provider") or
continue to contract for electricity service from the Electric Service Provider;
provided, however, that all Alternate Service Providers selected by Landlord
shall provide electricity service to the Building and Premises at a level which
is identical or better than the electricity service provided by the Electric
Service Provider and such new electricity service will not increase Tenant's
electricity costs.

          C.   Interruption of Services.  Unless repairs, renewals or
               ------------------------
improvements for services can be made during business hours without material
interference with Tenant's business operations, Landlord shall make such
repairs, alterations, or replacements during nonbusiness hours except in the
event of an emergency.  Landlord further agrees, where practical, to notify
Tenant in advance prior to the cessation of such service, and to estimate the
duration of such cessation.  Tenant also agrees to notify Landlord of any
interruption of services that Tenant discovers.

          If the Landlord ceases to furnish any of the services referred to in
this Paragraph 7 and if (i) as a result of such cessation, the Premises, or any
floor within the Premises, is rendered untenantable (meaning Tenant's inability
to use any or all of the floor(s) (or any part thereof) within the Premises in
the normal course of its business) and (ii) such cessation continues for a
period of three (3) business days, then, the Rent payable hereunder shall be
equitably abated based upon the

                                     -15-
<PAGE>

percentage of the space in the Premises so rendered untenantable and not then
being used by Tenant in the ordinary course of its business operations. The
foregoing abatement shall become effective as of the first business day
following the day the affected floor(s) become(s) untenantable. Landlord agrees
to use all commercially reasonable efforts to cure the cessation of service(s)
as promptly as reasonably practicable. Tenant agrees to cooperate with Landlord
in abiding by all reasonable rules and regulations that Landlord prescribes for
proper functioning of utilities and Building services. Tenant agrees not to
tamper or adjust any utilities or associated equipment unless authorized in
writing by Landlord.

          D.   Charges for Services.  Except as otherwise provided in this
               --------------------
Paragraph 7 or in Paragraph 5, all services shall be provided by Landlord and
the cost of providing such services shall be included in Operating Expenses.
Charges for any service for which Tenant is required to pay directly, rather
than by Tenant's  Expense Participation Amount, 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.

          E.   Energy Conservation.  Notwithstanding anything to the contrary in
               -------------------
this Paragraph 7 or elsewhere in this Lease, if the federal government, the
State of Illinois or the City of Chicago requires that temperature conditions be
maintained other than as set forth in Exhibit C, then Landlord shall be deemed
to be performing its obligation to furnish heating, ventilating and cooling
pursuant to the requirements of this Lease if it furnishes such heating,
ventilating and cooling as so required.  Landlord shall give Tenant notice of
such requirements as soon as reasonably possible after Landlord's receipt of
notice of such requirements.

     8.   REPAIRS.  Except to the extent that Landlord has the obligation to
          -------
rebuild pursuant to Paragraph 12 hereof, Tenant will, subject to Paragraph
11.A., at Tenant's own expense, perform any maintenance, repairs and
replacements of the Premises that are (i) caused by the neglect or misuse of
Tenant, its employees, contractors, agents, invitees or licensees, or (ii)
required to keep the floors, ceilings, walls, partitions, and other interior
portions of the Premises which are not a part of the Building's shared systems
in good repair and tenantable condition, reasonable wear and tear excepted.  If
the Tenant does not commence any such required maintenance, repair or
replacement within ten (10) days of the request of Landlord to do so, or if
after such commencement, Tenant does not thereafter diligently pursue same to
completion, Landlord may, but need not, make such repairs and replacements, and
Tenant shall pay Landlord the cost thereof.

          Landlord, as an Operating Expense (except as otherwise provided in
Paragraph 5), shall keep and maintain the Building and its fixtures,
appurtenances, systems and facilities serving the Premises, in good working
order, condition and repair and shall make all repairs, structural and
otherwise, interior and exterior, as and when needed in or about the Building
and the Premises, except for those repairs for which Tenant is responsible
pursuant to any other provisions of this Lease.  Without limiting the generality
of the foregoing, Landlord shall repair and maintain, and if necessary, replace
(i) building structure, foundation, roof, gutters, exterior walls, window
coverings, windows, and all other exterior and structural parts of the Building,
(ii) halls, stairways and entry ways, elevators and common passageways and all
other common areas of the Building, (iii) elevator

                                     -16-
<PAGE>

lobbies and restrooms on each floor of the Premises (provided Tenant has not
hired its own janitorial contractor to perform such repair and maintenance), and
(iv) all elements of the plumbing system, the sprinkler system, the light
fixtures and electrical distribution system, the heating, ventilating and air
conditioning system and any other of the Building's shared systems located
within the Premises. Nothing contained in this Paragraph 8 shall require
Landlord to paint or decorate the Premises. If the Landlord does not commence
any required maintenance, repair or replacement within thirty (30) days of the
request of Tenant to do so (or in cases of emergency within twenty-four (24)
hours after notice), or if after such commencement, Landlord does not thereafter
diligently pursue same to completion, Tenant may, but need not, make such
repairs and replacements, and Landlord shall pay Tenant the cost thereof within
ten (10) days after notice given from Tenant to Landlord specifying such costs.

          Except as expressly otherwise provided in this Lease, Landlord shall
have no liability to Tenant by reason of any inconvenience, annoyance,
interruption or injury to business arising from Landlord's making any repairs or
changes which Landlord is required or permitted by this Lease, or required by
law, to make in or to any portion of the Building or the Premises, or in or to
the fixtures, equipment or appurtenances of the Building or the Premises,
provided that Landlord shall use due diligence with respect thereto.  In case of
repairs or changes which are made within the Premises, unless such repairs,
renewals or improvements can be made during business hours without material
interference with Tenant's business operations, Landlord shall make such
repairs, alterations, or replacements during non-business hours, except in the
event of an emergency.

     9.   ADDITIONS AND ALTERATIONS.
          -------------------------

          A.   (i)  Tenant may, at its discretion and its expense, carpet and
decorate (i.e., paint, carpet, cover walls or ceilings, change furnishings,
change or move non-demising walls provided same does not affect any building
systems) and, if and as permitted by law, install an alarm and public address
system (provided such public address system does not create excessive noise
affecting other tenants and it is in compliance with all applicable codes) in
such portion of the "public stairways" as run between the floors comprising the
Premises and a door or other device barring access to such floors from lower
floors except in emergency.  Tenant may from time to time during the Term, at
its expense, make other alterations, additions, installations, substitutions,
and improvements (herein collectively called "changes") in and to the Premises,
excluding Structural Changes (as hereinafter defined), subject to the provisions
of this Paragraph 9.  If any changes performed by Tenant pursuant to this
Paragraph 9.A(i) require that a City of Chicago Building Permit be issued and
that drawings of such changes must  be submitted to the City of Chicago for the
issuance of the Building Permit, Tenant will provide Landlord with notice of
such changes and supply Landlord with a copy of the drawings for such changes
and the Building Permit. Notwithstanding anything to the contrary contained
herein, Landlord's approval is not required for any changes pursuant to this
Paragraph 9A(i).

          (ii) If the change involves any work which: (1) involves a
penetration or other alteration of the structural components of the Building,
including, but not limited to, floor slabs (other than electrical outlets), load
bearing walls or columns or demising walls, or (2) alters a

                                     -17-
<PAGE>

primary Building system which serves other premises within the Building
(collectively, "Structural Changes"), then Tenant shall, at least thirty (30)
days prior to commencing any Structural Changes, notify Landlord of the nature
and extent of such change and shall also submit reasonably detailed plans and
specifications with such notice showing all the planned changes. Tenant shall
not make any Structural Change without Landlord's prior consent, which consent
shall not be unreasonably withheld, and Landlord may impose reasonable
conditions with respect to Structural Changes, including, without limitation,
requiring Tenant to furnish Landlord with an itemization and security for the
payment of all costs to be incurred in connection with such changes, insurance
against liabilities which may arise out of such Structural Changes, plans and
specifications plus permits necessary for such changes and Landlord may require
that all contractors and subcontractors be approved in advance by Landlord,
which approval shall not be unreasonably withheld. The work necessary to make
any Structural Changes shall be done at Tenant's expense by Tenant's
contractors. Tenant shall reimburse Landlord for Landlord's reasonable and
actual costs in reviewing and approving work done by Tenant's contractors. Upon
completion of such work Tenant shall deliver to Landlord, if payment is made
directly to contractors, evidence of payment, contractors' affidavits and full
and final waivers of all liens for labor, services or materials all in form
reasonably satisfactory to Landlord. Tenant shall defend and hold Landlord and
the Land and Building harmless from all costs, damages, liens and expenses
related to changes made by Tenant or its contractors, and relating to non-
payment by Tenant of the cost of such changes. All work done by Tenant or its
contractors pursuant to Paragraphs 8 or 9 shall be done in a first-class
workmanlike manner using only good grades of materials and shall comply with all
insurance requirements and all applicable laws and ordinances and rules and
regulations of governmental departments or agencies. In hiring such contractors,
Tenant will not knowingly take any action which will directly result in
picketing of the Building or the concerted withholding of services by any
employees of Landlord or Landlord's beneficiary and should any such action occur
Tenant will take any reasonable steps available to bring such action to an end.

          B.   All changes, whether temporary (to the extent then existing) or
permanent in character, made or paid for by Landlord or Tenant, shall without
compensation to Tenant become Landlord's property at the termination of this
Lease by lapse of time or otherwise.  Tenant shall remove any Structural Changes
and restore the Premises to their condition existing prior to such Structural
Changes on or before the termination of this Lease if Landlord notified Tenant
at the time Landlord approved the making of such Structural Changes that
Landlord required such removal. Except for the aforementioned limited obligation
of Tenant to remove certain Structural Changes, upon termination of this Lease,
Tenant shall have no obligation to remove any changes and to restore the
Premises to their condition prior to such changes.

     10.  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 the Premises
with respect to work or services claimed to have been performed for or materials
claimed to have been furnished to

                                     -18-
<PAGE>

Tenant or to the Premises by contractors retained by Tenant, and, in case of any
such lien attaching, or claim thereof being asserted, Tenant covenants and
agrees within thirty (30) days of learning thereof to cause it to be released
and removed of record or to be bonded over by a title insurer or surety
reasonably satisfactory to Landlord. In the event that any such lien is not so
released and removed or bonded over, Landlord, at its sole option, may take all
action necessary, and to investigate the validity thereof, to release and remove
such lien, and Tenant shall promptly, upon notice, reimburse Landlord for all
reasonable sums, costs and expenses (including reasonable attorneys' fees)
incurred by Landlord in connection with the release and removal of such lien.

     11.  INSURANCE.
          ---------

          A.   Waiver of Subrogation.  Subject to the limitations set forth
               ---------------------
below in this Paragraph 11.A., Landlord and Tenant each hereby waive any and
every claim for recovery from the other for any and all loss or damage to the
Building or Premises or to the contents thereof, which loss or damage is covered
by the provisions of any insurance policy carried, or would have been covered by
the provisions of any insurance policy required to be carried, by either party
pursuant to this Lease.  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 use their best
efforts to have such insurance policies properly endorsed, if necessary, to
prevent the invalidation of such insurance coverage by reason of such waiver.
In the event that either party's insurer shall refuse to permit such waiver or
agreement even with an additional charge, then, so long as the addition of the
other party as an additional named insured is permitted and does not reduce the
amount recoverable under the terms of the policy by the insuring party or
otherwise adversely affect the insurance coverage, the insuring party shall add
the other party as an additional insured.  If either party's insurer shall
refuse both (i) to permit such waiver or agreement even with an additional
charge and (ii) to name the other party as an additional insured without
adversely affecting the insurance coverage, then, the mutual waivers contained
in the first sentence of this Paragraph 11.A. will no longer be effective.

          B.   Tenant's Coverage.  Tenant shall purchase and maintain insurance
               -----------------
during the entire Term 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, in all cases subject to a reasonable
deductible, but initially Tenant shall maintain the following coverages in the
following amounts:

          (1)  Commercial General Liability Insurance covering the Tenant (and
     naming as additional insureds the Landlord, any trust or trusts which may
     hold title to the Land and any beneficiary or beneficiaries thereof) for
     claims of bodily injury, personal injury and property damage arising out of
     Tenant's operations, or use of the Premises, for limits of liability not
     less than:

     Bodily Injury Liability        $5,000,000 each occurrence
                                    $5,000,000 annual aggregate

                                     -19-
<PAGE>

     Personal Injury Liability      $5,000,000 annual aggregate

     Property Damage Liability      $1,000,000 each occurrence
                                    $1,000,000 annual aggregate

          (2)  Physical Damage Insurance covering all Tenant improvements within
     the Premises (not including the Base Building, all structural components of
     the Building and all Building systems except for supplementary portions of
     such systems as are owned by Tenant) and all subsequent additions,
     improvements and alterations owned or made by Tenant, and all office
     furniture, furnishings, trade fixtures, office equipment, merchandise and
     all other items of Tenant's property on the Premises.  Such insurance shall
     be written on an "all risks" of physical loss or damage basis, for the full
     replacement cost value of the covered items in amounts that meet any
     coinsurance clauses of the policies of insurance.  Tenant shall deliver to
     Landlord certificates of such insurance evidencing the coverages required
     in (B)(1) and (B)(2) hereof in form reasonably satisfactory to Landlord,
     which certificates shall in each case state that such insurance may not be
     canceled without at least thirty (30) days' prior written notice to
     Landlord.

          C.   Landlord's Coverage.  Landlord hereby agrees to insure the
               -------------------
Building and all portions of the Premises not required to be insured by Tenant
during the Term on an "all risks" of physical loss or damage basis including
boiler and machinery coverage, in an amount that meets any coinsurance clauses
of the policy and is equal to one hundred percent (100%) of the full replacement
cost of the Building (excluding the cost of foundation, excavation and footings
below the lowest basement floor) subject to a reasonable deductible.  Landlord
shall carry rent loss insurance in an amount equal to not less than twelve (12)
months of gross Building rents and earthquake/flood insurance in an amount
customary for first-class office buildings in Chicago, Illinois.  Landlord shall
also carry Commercial General Liability Insurance with at least the same
coverages and amounts as required of Tenant above.  All insurance policies shall
include cross liability and severability of interest endorsements.  Landlord
shall deliver to Tenant, certificates of such insurance in form reasonably
satisfactory to Tenant, which certificates shall in each case state that such
insurance may not be canceled or materially changed without at least thirty (30)
days' prior written notice to Tenant, and said insurance policies shall be
endorsed so that such insurance policies may not be canceled or materially
changed without at least thirty (30) days' prior written notice to Tenant.  All
insurance policies shall be with an insurance company having an A.M. Best Rating
of A- XII or better or an insurance company of equivalent financial standing.

          D.   Workmen's Compensation Coverage.  Both Landlord and Tenant shall
               -------------------------------
carry Workmen's Compensation coverage at such times and in such amounts as may
be required by applicable statutes, and at the request of the other party, shall
supply a certificate evidencing such coverage.

          E.   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 which may thereby

                                     -20-
<PAGE>

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 by reason of the failure of Tenant to comply with the
provisions of this Paragraph 11.E., any insurance coverage is jeopardized or
insurance premiums are increased, Landlord shall have the option, if the
insurance coverage is jeopardized, to enjoin the use which jeopardizes the
coverage, and if the insurance premium is increased, to require Tenant to make
immediate payment of the increase.

     12.  FIRE OR CASUALTY.
          ----------------

          If the Building or the Premises shall be partially or totally damaged
or destroyed or rendered untenantable by fire or other cause at any time during
the first ten (10) Calendar Years of the Term, Landlord shall be obligated and
shall proceed with reasonable diligence to repair the damage and restore and
rebuild the Building and the Premises at its expense as promptly as reasonably
practicable; provided, however, that Landlord shall not be required to repair or
replace any property required to be insured by Tenant pursuant to Paragraph
11.B.(2).

          In the event Landlord is obligated pursuant hereto to restore and
rebuild the Premises, or any portion thereof, as a result of a fire or other
cause, Landlord shall be obligated to restore or rebuild those portions of the
improvements in the Premises or the affected portion thereof, which would be
Landlord's property upon termination of the Lease to the condition they were in
immediately prior to such damage or destruction, except that the replacement
items shall be new rather than used.

          If the Premises, or any portion thereof, shall be rendered
untenantable as a result of fire or other cause, all Rents payable hereunder
shall be equitably abated to the extent that the Premises shall have been
rendered untenantable, such abatement to be for the period from the date of such
damage or destruction to the Premises to the date the Premises are no longer
untenantable.

          If, at any time after the first ten (10) years Calendar Years of the
Term, less than 50% of  the Building shall be rendered untenantable by fire or
other casualty, Landlord shall be obligated and shall proceed with reasonable
diligence to repair the damage and restore and rebuild the Building and the
Premises at its expense; provided, however, that Landlord shall not be required
to repair or replace any property required to be insured by Tenant pursuant to
Paragraph 11.B.(2).

          If, at any time after the first ten (10) Calendar Years of the Term,
50% or more of  the Premises or the Building shall be rendered untenantable or
inaccessible by fire or other casualty, Landlord shall notify Tenant within one
hundred twenty (120) days after the date of such fire or other casualty of
Landlord's reasonable estimate for the amount of time from the date of such fire
or other casualty necessary to make the required repairs and tender the Premises
to Tenant (the "Rebuild Notice").  Provided Tenant is not in default hereunder
(beyond any applicable cure period), Tenant may, upon notice to Landlord within
thirty (30) days after Tenant's receipt of the Rebuild Notice, obligate Landlord
to repair the damage and restore the Premises at Landlord's expense (the
"Obligation Notice") as promptly as reasonably practicable; provided, however,
that Tenant's

                                     -21-
<PAGE>

Obligation Notice shall be effective only if at the time of service of such
notice, the following conditions (the "Rebuild Conditions") shall be satisfied:

          A.   Tenant shall exercise its option on the first Extension Term as
provided in Paragraph 34 of this Lease; provided, however, that the term of such
first Extension Term shall be increased to the extent necessary to extend the
Term of this Lease so that there shall be a total of ten (10) years remaining in
the Term of the Lease (measured from the date Landlord delivers the restored
Premises to Tenant); and

          B.   Tenant shall waive its contraction options under Paragraph 31 of
this Lease.

Provided the Obligation Notice is effective, Landlord shall be obligated and
shall proceed with reasonable diligence to repair the damage and restore and
rebuild the Building and the Premises at Landlord's expense; provided, however,
that Landlord shall not be required to repair or replace any property required
to be insured by Tenant pursuant to Paragraph 11.B.(2).  If Tenant does not
provide Landlord with the Obligation Notice within thirty (30) days of Tenant's
receipt of the Rebuild Notice, Landlord shall have no obligation to rebuild the
Premises, and Landlord may, at its option, terminate this Lease by giving
written notice thereof to Tenant.  In the event that such notice of termination
shall be given, this Lease shall terminate as of the date provided in such
notice of termination with the same effect as if that date were the expiration
date of the Term.

          Any dispute which may arise between the parties with respect to the
meaning or application of any of the provisions of this Paragraph 12 shall be
determined by a partner at an architectural firm acceptable to Landlord and
Tenant whose fees and expenses shall be borne equally by Landlord and Tenant
("Architect").  If Landlord and Tenant cannot agree on an Architect, then each
shall select an architect and the two architects shall select a third architect
whose decision shall be binding on the parties.


     13.  WAIVER OF CLAIMS.  Neither Landlord nor Landlord's beneficiaries, nor
          ----------------
the agents, officers, directors, shareholders, partners or principals (disclosed
or undisclosed) of either of them shall be liable to Tenant or Tenant's
shareholders, agents, employees, invitees, licensees or other occupants of the
Premises, for any injury or damage to, or loss (by theft or otherwise) of any of
Tenant's property or of the property of any other person, irrespective of the
cause of such injury, damage or loss (including the acts or negligence of any
tenant or of any owners or occupants of adjacent or neighboring property or
caused by operations in construction of any private, public or quasi-public
work) unless due to the negligence of Landlord, or Landlord's beneficiaries or
the agents, officers, directors, partners, principals (disclosed or undisclosed)
or employees of either of them as to matters required to be insured by Landlord
under this Lease, or due to the negligence of Landlord, or Landlord's
beneficiaries or the agents, officers, directors, partners, principals
(disclosed or undisclosed) or employees of either of them as to all other
matters. Neither Tenant, nor Tenant's shareholders, agents, employees, invitees,
licensees or other occupants of the Premises shall be liable to Landlord,
Landlord's beneficiaries, or the agents, officers, directors, shareholders,
partners or

                                     -22-
<PAGE>

principals (disclosed or undisclosed) of either of them for injury or damage to,
or loss (by theft or otherwise) of any of the property of any other person,
irrespective of the cause of such injury, damage or loss (including the acts of
negligence of any tenant or any owners or occupants of the adjacent or
neighboring property or caused by operations in construction of any private,
public or quasi-public work) unless due to the negligence of Tenant or Tenant's
shareholders, agents or employees, as to matters required to be insured by
Tenant or due to the negligence of Tenant or Tenant's shareholders or agents, as
to all other matters. Landlord, Landlord's beneficiaries, and the agents,
officers, directors, partners or principals (disclosed or undisclosed) of either
of them shall not be liable, to the extent of Tenant's recovery under any
insurance carried by it, whether or not required to be carried by the terms of
this Lease, for any loss or damage to any person or property even if due to the
negligence of Landlord, Landlord's beneficiaries or the agents, officers,
directors, partners or principals (disclosed or undisclosed) of either of them.
Similarly, Tenant and Tenant's shareholders, agents, employees, invitees,
licensees or other occupants of the Premises shall not be liable to Landlord, or
Landlord's beneficiaries to the extent of Landlord's or Landlord's
beneficiaries' recovery under any insurance carried by it, whether or not
required to be carried by the terms of this Lease, for any loss or damage to any
person or property even if due to the negligence of Tenant or Tenant's
shareholders, agents, employees, invitees, licensees or other occupants of the
premises. Landlord and Tenant shall each make all reasonable efforts to recover
from its insurers any claim which may provide a recovery to the other.

     14.  NONWAIVER.  No waiver of any provision of this Lease shall be implied
          ---------
by any failure of Landlord or Tenant to enforce any remedy on account of the
violation of such provision, even if such violation be 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 giving of 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 such
Rent shall not waiver or affect such notice, suit or judgment.

     15.  CONDEMNATION.  If all or substantially all of the Land and the
          ------------
Building (herein in this Paragraph 15 sometimes collectively called the
"Project") is taken by condemnation permanently, or for a period in excess of
one (1) year, this Lease shall terminate automatically.

          If the taking is of less than substantially all of the Project or is
for a period of less than the aforesaid year, and if this Lease is for any
reason not terminated pursuant to the following grammatical paragraph, Landlord
shall as soon as possible (but in no event longer than one (1) year) restore the
Project as nearly as can practicably be done (including the Premises) using all
of the award received by Landlord (but not in excess thereof) so as to provide
to the extent reasonably possible comparable space and amenities to those
enjoyed by Tenant under this Lease prior to the taking (or Tenant's
Proportionate Share thereof in case of the application of subparagraph B below);
in such event this Lease shall continue in force at the square foot rental rates
and adjustment herein

                                     -23-
<PAGE>

provided for the Premises applied to the RSF of the Premises existing in the
Project as restored (or Tenant's Proportionate Share thereof in case of the
application of subparagraph B below), but rent shall abate as to periods when
the Premises is not available for normal use by Tenant as a result of such
taking and work of restoration.

          If the taking is of less than substantially all of the Project or is
for a period of less than the aforesaid year, then notwithstanding the foregoing
grammatical paragraph, Landlord and Tenant shall have the right to terminate
this lease in the following circumstances:

          A.   Landlord may terminate if in Landlord's reasonable business
judgment restoration of the Project to substantially the same size and quality
is not economically justified;

          B.   Tenant may terminate if (1) more than twenty-five percent (25%)
of the Premises is so taken by eminent domain and (2) within sixty (60) days
after such taking Landlord has not been able to provide other comparable space
in the Building to temporarily add to the Premises to restore the size of the
Premises to at least eighty-five percent (85%) of its Rentable Area prior to
such taking and Landlord will not, based on Landlord's estimate of the Rentable
Area of the restored Building (such estimate to be delivered to Tenant not more
than forty-five (45) days after such taking), be able to restore the Premises to
100% of their Rentable Area prior to such taking by a date not more than one
year after the date of such taking.  Landlord shall not be bound to offer Tenant
more than Tenant's Proportionate Share (based on the Premises compared to the
Building prior to such taking) of the restored Building, and if Tenant fails to
terminate this Lease as provided herein, the size of the Premises and the Rent
shall be reduced to such share of the restored Building;

          C.   Either Landlord or Tenant may terminate if the taking occurs
within twenty-four (24) months prior to the then effective termination date of
the Term, as it may have been extended.

          In any of the above termination cases, such termination notice must be
given not more than sixty (60) days after the taking (the taking for purposes of
this Paragraph shall be the date when the taking authority requires possession)
and termination must be effective for the portion not taken not less than thirty
(30) or more than ninety (90) days after such notice is given.  For the portion
taken, the termination shall be effective as of the date of the taking.  No
money or other consideration shall be payable by the Landlord to the Tenant in
the case of termination under any of the above provisions, and Tenant shall have
no right to share in the condemnation award except that Tenant shall have the
right to recover out of the award all costs and expense incurred by Tenant in
moving to other space and the amount of the unamortized cost of all improvements
and additions located in the Premises (not including the Allowance contributed
by Landlord).

     16.  ASSIGNMENT AND SUBLETTING.
          -------------------------

          A.   Except as provided below, Tenant shall not, without the prior
written approval of Landlord, which approval shall not be unreasonably withheld,
(i) assign, convey or mortgage this Lease or any interest hereunder; (ii) permit
to occur or permit to exist any assignment of this Lease

                                     -24-
<PAGE>

or (unless bonded or insured over as provided in Paragraph 10 hereof) any lien
upon Tenant's interest, voluntarily or by operation of law; (iii) sublet space
in the Premises; or (iv) except in the case of (iii) above, permit the use of
the Premises by any parties other than (a) Tenant and any Affiliate (as
hereinafter defined) of Tenant, and (b) shareholders, employees and invitees of
any of the foregoing. There shall be no partial assignment of Tenant's interest
in this Lease. Any assignment of 100% thereof shall be governed by Paragraph
16.E. Except as provided in Paragraph 16.B., the word "assignment" in this
Paragraph shall mean a 100% assignment. The term "sublease" and all words
derived therefrom, as used in this Paragraph 16, shall include any subsequent
sublease or assignment under such sublease. Notwithstanding anything to the
contrary contained herein, Landlord's approval of any sublease by Tenant
pursuant to (iii) above shall be limited to Landlord's reasonable approval of
the identity of the proposed subtenant, and the approval conditions listed in
the final sentence of the following paragraph.

          Landlord's election to accept any assignee or subtenant as the tenant
hereunder and to collect rent from such assignee or subtenant shall not release
Tenant or any subsequent tenant from any covenant or obligation under this Lease
except as may be expressly provided in Landlord's written consent.  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, including assignment, subletting or transfer by any subtenant.
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.
To obtain the consent of Landlord to an assignment or subletting, Tenant shall
submit to Landlord at least thirty (30) days prior to the proposed effective
date of the assignment or sublease a written notice thereof.  Landlord shall not
be deemed to have unreasonably withheld its consent to a proposed sublease or
assignment if its consent is withheld because: (1) Tenant is then in default
hereunder (beyond any applicable cure period); (2) any notice of termination of
this Lease or termination of Tenant's possession shall have been given pursuant
hereto and the matter or occurrence giving rise to such notice has not been
cured; (3) the proposed sublease or assignment will, as proposed, violate any
city, state or federal law, ordinance or regulation; (4) the proposed use of the
Premises by the subtenant or assignee does not conform to the use set forth in
Paragraph 6 hereof; or (5) the proposed subtenant or assignee is engaged in a
business that would be deleterious to the reputation of the Building.

          B.   Landlord shall be deemed to approve of any assignment or sublease
(however Tenant shall notify Landlord of such assignment or sublease) to: (i)
any party resulting from a merger or consolidation with Tenant so long as Tenant
or any Affiliate (as hereinafter defined) is the surviving dominant party after
such merger; (ii) any party succeeding to the business and assets of Tenant; or
(iii) any Affiliate of Tenant.  For purposes of this Lease, an "Affiliate" shall
mean any firm, person, corporation or entity now or hereafter controlling,
controlled by or under common control with Tenant and such control is exercised
via the ability to direct or cause the direction of, the management and policies
of the other, whether through the ownership of voting securities, common
directors or officers, or otherwise.  At any time during the Term of this Lease,
if Tenant transfers all or a part of Tenant's United States business operations
as of October 1, 1997 (the "U.S. Business") to an Affiliate or any other firm,
person, corporation or entity (collectively, a "Successor

                                     -25-
<PAGE>

Entity"), such Successor Entity shall be made a party to this Lease and shall be
jointly responsible with Tenant for all obligations under this Lease. The
previous sentence shall apply to any transferee of any such Successor Entity,
unless Tenant or any Successor Entity provides Landlord with reasonably
acceptable credit documentation evidencing Tenant's and any Successor Entity's
financial capacity to perform their obligations under this Lease.

          C.   If at any time Tenant subleases (each sublease, a "Tenant
Sublease") up to a total of 200,000 square feet of space in the Premises,
"Sublease Profits" (as defined in Paragraph 16.D.) shall be allocated in the
following manner:

               (i)   If there is 150,000 or more RSF then available for lease in
     the Building at the time of execution of a Tenant Sublease, Landlord and
     Tenant shall divide Sublease Profits between them equally.

               (ii)  If there is less than 150,000 RSF then available for lease
     in the Building at the time of execution of a Tenant Sublease, Tenant shall
     retain 100% of all Sublease Profits.

Notwithstanding the foregoing, if Tenant subleases more than 200,000 square feet
of space in the Premises, the Sublease Profits for the portion of such space
above 200,000 square feet shall be equally divided between Landlord and Tenant,
regardless of the amount of vacant space in the Building at the time of the
sublease.  Calculations of Sublease Profits and sublease RSF percentage
limitations shall be made on a monthly basis throughout the Term.

          D.   "Sublease Profits" shall mean the entire excess, after deduction
of all reasonable costs of subletting (including, without limitation, marketing
costs, rent concessions, reasonable attorneys' fees, commissions and tenant
improvement allowances), of revenues generated by the subleasing of the Premises
or portions thereof over the Rent applicable thereto.  All such revenues shall
be applied first to reimbursement of such costs of subletting until they are
paid in full. Not more than thirty (30) days after the commencement date of a
sublease which will produce Sublease Profits and annually thereafter, Tenant
shall furnish Landlord with a sworn statement setting forth in detail the
computation of the Sublease Profits on such sublease (which computation shall be
based upon generally accepted accounting principles).

          Every such statement shall be conclusive and binding upon Landlord as
to the Sublease Profits paid prior to the date of such statement unless within
thirty (30) days after the receipt of such statement, Landlord shall notify
Tenant that it disputes the correctness of the statement, specifying the
particular respects in which the statement is claimed to be incorrect.  If such
dispute shall not have been settled by agreement within thirty (30) days after
delivery of Landlord's dispute notice, it shall be settled by submission of such
dispute to a national public accounting firm acceptable to Landlord and Tenant,
at the expense of Landlord, except as hereinafter provided, for a final and
binding determination.   Upon determination of such dispute, such Sublease
Profits shall be recalculated and any overpayment shall be returned, or
underpayment promptly made, on demand plus interest on such overpayment or
underpayment at the rate of two percent (2%)

                                     -26-
<PAGE>

per annum over the Prime Rate. Tenant agrees to grant Landlord reasonable access
to Tenant's office for the purpose of verifying Sublease Profits and to make
copies of any and all bills, vouchers and other documents relating thereto,
subject to reimbursement by Landlord for the cost of such copies. In the event
that a review of Tenant's books and records pursuant to this Paragraph reveals
that Tenant has understated Sublease Profits by in excess of five percent (5%)
of the actual Sublease Profits payable to Landlord, Tenant shall also reimburse
Landlord for the reasonable expenses incurred by Landlord in conducting such
review of Tenant's books and records and the accounting firm costs. If a part of
the consideration for any subletting shall be payable other than in cash, the
payment to Landlord shall be payable in cash based on the cash value of the
other non cash considerations. Tenant shall pay Landlord its share of the
Sublease Profits promptly upon Tenant's receipt from time to time of periodic
payments from a subtenant or at such other time as Tenant shall realize the
Sublease Profits from such sublease. Landlord shall not be responsible for any
deficiency in amounts received for a sublease in relation to the Rent due
hereunder.

          E.   In case Tenant proposes to Landlord an assignment of 100% of its
interest in this Lease by the notice described in Paragraph 16.A. hereof,
Landlord shall have the option to terminate this Lease.  If Landlord wishes to
exercise its option to terminate, Landlord shall, within fifteen (15) days after
Landlord's receipt of the notice from Tenant described in Paragraph 16.A., send
to Tenant a notice of termination.  The date on which such termination will be
effective shall be the proposed commencement date of the assignment.  Tenant
shall automatically be released from all obligations under this Lease to be
performed after the effective date of such termination. Landlord shall have no
option to terminate this Lease for assignments or sublets pursuant to Paragraph
16.B. hereof.

          If Landlord approves such assignment but does not so terminate this
Lease, Tenant may proceed with the proposed assignment.  Landlord and Tenant
shall share in the ratio of 50% to 50% the profits from said assignment
calculated and verified in the same fashion as described in Paragraph 16.D.
above.

     17.  SURRENDER OF POSSESSION.  On the last day of the Term, or upon any
          -----------------------
earlier termination of this Lease, or upon any re-entry by Landlord upon the
Premises, Tenant shall quit and surrender the Premises to Landlord.  Tenant
shall remove all of Tenant's trade fixtures, furniture and other personal
property therefrom, shall restore the Premises wherever such removal results in
damage thereto and shall otherwise generally leave the Premises in a reasonably
tenantable condition.  Any interest of Tenant in the alterations, improvements
and additions to the Premises shall, without compensation to Tenant, become
Landlord's property at the termination of this Lease by lapse of time or
otherwise and such alterations, improvements and additions shall be relinquished
to Landlord.  Tenant shall remove alterations, additions and improvements and
make such restorations to the Premises as are required pursuant to Paragraph
9.B. herein.

     If Tenant shall fail or refuse to remove any of Tenant's property from the
Premises, Tenant shall be conclusively presumed to have abandoned the same, and
title thereto shall thereupon pass to Landlord without any cost either by
setoff, credit, allowance or otherwise.

                                     -27-
<PAGE>

     18.  HOLDING OVER.  Tenant shall pay to Landlord Rent at an annual rate
          ------------
equal to the greater of (i) Current Market Rate for the Premises, determined, if
necessary, in accordance with Paragraph 30.G. hereof, or (ii) one hundred fifty
percent (150%) of then current Base Rent for the Premises, plus one hundred
fifty percent (150%) of the Additional Rent paid by Tenant during the previous
Calendar Year herein provided, payable in monthly installments on the first day
of each month or portion thereof for which Tenant shall retain possession of the
Premises or any part 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 also pay all damages sustained by Landlord by reason of such retention if
such retention shall continue for thirty (30) or more days.

     19.  ESTOPPEL CERTIFICATE.  Landlord and Tenant each agree, from time to
          --------------------
time upon not less than ten (10) days' prior request by the other party, to
execute, acknowledge and deliver to the other party 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) whether the Term has
commenced and the dates to which Rent and other charges have been paid; (iii)
that the other party is not in default under any provision of this Lease, to the
knowledge of the party furnishing the certificate, or if in default, the nature
thereof in detail (and in case of certificates requested of Tenant, that, to the
best knowledge of Tenant, Tenant has no existing defenses, set-offs, or claims
hereunder, or, if any, specifying same); and (iv) such further matters as
reasonably may be requested, it being intended that any such statement may be
relied upon by any prospective assignee or sublessee of any tenant (including
Tenant) of the Building, any mortgagees or prospective mortgagees thereof, any
lender to Tenant, or any prospective and/or subsequent purchaser or transferee
of all or part of Landlord's interest in the Land and/or Building or of Tenant's
interest in the Premises.

     20.  SUBORDINATION.  This Lease shall be prior to any mortgage or ground or
          -------------
underlying lease; provided, however, Tenant agrees to subordinate its rights
hereunder at all times to (i) the lien of any mortgage or mortgages designated
by Landlord and to all advances made or thereafter made upon the security
thereof, and (ii) to all future ground leases or underlying leases of the Land
and the Building designated by Landlord and to execute any such reasonable
agreements evidencing such subordination as may be reasonably required by the
mortgagee, trustee or ground or underlying lessor, as the case may be, and to
attorn to and to recognize, as Landlord, the purchaser at a foreclosure sale or
the mortgagee, trustee or its nominee in the event the mortgagee, trustee or
such nominee accepts a deed in lieu of foreclosure, or the ground or underlying
lessor in the event of the termination of such underlying or ground lease in
return for and upon delivery to Tenant by such mortgagee, trustee or ground or
underlying lessor, as the case may be (each being referred to as a "Lender"), of
an agreement in a form reasonably satisfactory to Lender and Tenant providing
that in the event of a foreclosure of such mortgage or the giving of a deed in
lieu of foreclosure or termination of such ground or underlying lease, this
Lease shall not be terminated and Tenant may remain in possession of the
Premises pursuant to the terms of this Lease and retain all of the rights,
options and privileges granted to it hereunder as long as Tenant continues to
perform its obligations hereunder and further providing that the purchaser at a
foreclosure sale or transferee in the case of a deed in lieu of foreclosure or
ground or underlying lessor, as the case may be, will assume all of the
obligations of Landlord in such case; provided, however, that the holder of any
mortgage, or

                                     -28-
<PAGE>

purchaser at any foreclosure sale, as the case may be, shall not be bound by any
prepayment of Base Rent or Additional Rent which Tenant may have paid in excess
of the amounts then due for the current month (the "SNDA"). Tenant agrees to
enter into an SNDA with any future Lender whose terms are no less favorable to
Lender than those contained in the SNDA entered into between Tenant and Citicorp
Real Estate, Inc. concurrently herewith.

          Tenant also agrees to give any holder of any first mortgage, by
registered or certified mail, a copy of any notice or claim of default served
upon the Landlord by Tenant, provided that prior to such notice Tenant has been
notified in writing (by way of service on Tenant of a copy of an assignment of
Landlord's interests in leases, or otherwise) of the address of such first
mortgage holder.

     21.  CERTAIN RIGHTS RESERVED BY LANDLORD.
          -----------------------------------

          A.   Landlord shall have the following rights 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 claims:

          (1)  To install, affix and maintain any and all signs on the exterior
     and on the interior of the Building; except that there shall be no signs
     for retail or commercial tenants in the lobby of the office portion of the
     Building and, other than for a tenant then having 400,000 RSF or more under
     lease ("Large Tenant"), there shall be no sign on the exterior of the
     Building indicating the occupancy of any tenant in the Building without the
     approval of Tenant which it may reasonably withhold.  If there shall be a
     sign proposed for a Large Tenant, Tenant shall have the right to approve:
     (i)  the installation of the sign and (ii) the text, location, size and
     style of such sign, such approvals not to be unreasonably withheld or
     delayed, and Tenant shall also have the right to equivalent signage.  All
     Tenant's rights to approve under this subparagraph shall exist only so long
     as Tenant (including any Affiliate or Successor Entity) is not in default
     hereunder (beyond any applicable cure period) and occupies at least 400,000
     RSF in the Building.  Landlord hereby approves all Tenant signage existing
     as of the date hereof.  Landlord shall have the right to approve (which
     approval not to be unreasonably withheld) all additional lobby or exterior
     signage proposed by Tenant and not existing as of the date hereof.

          (2)  To decorate or to make repairs, alterations, additions, or
     improvements, whether structural or otherwise, in and about the Building,
     or any part thereof, and for such purposes to enter upon the Premises, and
     during the continuance of any of such 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 Premises are
     accessible and usable and provided that Landlord shall use due diligence
     with respect thereto.  Unless such repairs, renewals or improvements can be
     made during business hours without material interference

                                     -29-
<PAGE>

     with Tenant's business operations and, except in the case of an emergency,
     Landlord shall make such repairs, alterations, or replacements during non-
     business hours;

          (3)  To furnish door keys or magnetic cards 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 magnetic cards to all doors
     within and into the Premises; provided that such system will permit the
     Landlord upon request of Tenant to cancel the effectiveness of the card
     held by any shareholder or employee or invitee of Tenant upon such person's
     departure from Tenant or for any other reason.  Tenant agrees to purchase
     only from Landlord additional duplicate keys or magnetic cards as required
     (at Landlord's actual cost for such keys or magnetic cards), to change no
     locks or magnetic card readers, and not to affix locks or magnetic card
     readers on doors without the prior written consent of the Landlord not to
     be unreasonably withheld; provided that Landlord shall respond to Tenant's
     request for such consent with reasonable promptness.  Upon the expiration
     of the Term or Tenant's right to possession, Tenant shall return all keys
     or magnetic cards to Landlord and shall disclose to Landlord the
     combination of any safes, cabinets or vaults left in the Premises;

          (4)  To designate a building standard window covering for exclusive
     use throughout the Building;

          (5)  To approve the weight, size and location of safes, vaults,
     library shelving, file storage equipment 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 reasonably direct in writing. Tenant shall
     not install or operate machinery or any mechanical devices of a nature not
     directly related to Tenant's ordinary use of the Premises without the prior
     written consent of Landlord, not to be unreasonably withheld;

          (6)  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;

          (7)  To reasonably regulate delivery and service of supplies and the
     usage of the loading docks, receiving areas and freight elevators;

          (8)  To show the Premises to prospective tenants within the final
     twelve (12) months of the Term (as the same may be extended), at reasonable
     times, and in a manner not to interfere with Tenant's use and enjoyment of
     the Premises and, if vacated or abandoned, to show the Premises at any time
     and to prepare the Premises for reoccupancy;

                                     -30-
<PAGE>

          (9)  To erect, use and maintain pipes, ducts, wiring and conduits, and
     appurtenances thereto, in and through the Premises at reasonable locations
     that do not unreasonably interfere with Tenant's business;

          (10) To enter the Premises at any reasonable time upon reasonable
     prior notice (except no notice shall be required in the case of emergency)
     to inspect the Premises;

          (11) Only Landlord or one or more persons approved by Landlord will be
     permitted to furnish bootblacking and barbering.  Landlord may fix the
     hours during which, and the regulations under which, such supplies and
     services are to be furnished.  Landlord expressly reserves the right to act
     as, or to designate, at any time and from time to time, an exclusive
     supplier of all or any one or more of said supplies and services, provided
     all such supplies and services shall be furnished on a basis which is
     reasonably competitive to that which would otherwise be directly available
     to Tenant; and Landlord furthermore expressly reserves the right to exclude
     from the Building any person attempting to furnish any of said supplies or
     services but not so designated by Landlord.  Notwithstanding the foregoing,
     Tenant shall have the right to specify the vendors for other supplies and
     services for the Premises, subject to Landlord's approval, which approval
     shall not be unreasonably withheld or delayed;

          (12) To close the Building after hours and on any day which is not a
     business day, subject, however, to Tenant's right to admittance to the
     Premises at any time under such reasonable regulations as Landlord may
     prescribe from time to time, which may include but shall not be limited to,
     a requirement that persons entering or leaving the Building identify
     themselves to a watchman by registration or otherwise and establish their
     right to enter or leave the Building.

     22.  RULES AND REGULATIONS.  Tenant agrees to observe the Rules and
          ---------------------
Regulations for Tenant attached hereto as Exhibit E and made a part hereof.
Landlord shall have the right from time to time to prescribe additional rules
and regulations 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 such rules and regulations, provided such
rules and regulations are uniformly enforced against all Building tenants and
except to the extent that such rules and regulations unreasonably contradict or
abrogate any right or privilege herein expressly granted to Tenant. Landlord
will provide Tenant with a written copy of any modifications to the Rules and
Regulations.

     23.  REMEDIES.  If default shall be made in the payment of the Rent or any
          --------
installment thereof or in the payment of any other sum required to be paid by
Tenant under this Lease and such default shall continue for ten (10) days after
written notice to Tenant; or if default shall be made in the observance or
performance of 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, unless with respect to any non-
monetary default which cannot be cured within thirty (30) days, Tenant, in good
faith, promptly after receipt of such notice, shall have

                                     -31-
<PAGE>

commenced and thereafter shall continue diligently to reasonably prosecute and
complete all action necessary to cure such default within an additional forty-
five (45) days; or if a default which involves a hazardous condition is not
cured by Tenant as promptly as reasonably possible upon written notice to
Tenant; or if any involuntary petition in bankruptcy shall be filed against
Tenant under any federal or state bankruptcy or insolvency act and shall not
have been dismissed within ninety (90) days from the filing thereof, or if a
receiver shall not have been dismissed within ninety (90) days from the date of
his appointment, or if Tenant shall make an assignment for the benefit of
creditors, or if Tenant shall admit in writing Tenant's inability to meet
Tenant's debts as they mature, the levy upon execution or the attachment by
legal process of the leasehold interest of Tenant or the filing or creation of a
lien in respect of such leasehold interest, which lien shall not be released or
discharged within thirty (30) days after the date of filing, bankruptcy,
reorganization, insolvency or liquidation proceedings, or other proceedings for
relief under any bankruptcy law are instituted by or against Tenant and not
dismissed within ninety (90) days after institution, then Landlord may treat the
occurrence of any one or more of the foregoing events as a breach of this Lease,
and thereupon at its option may, with or without any additional 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:

          (1)  Landlord may terminate this Lease and the Term created hereby, in
     which event Landlord may forthwith repossess the Premises and be entitled
     to recover forthwith, as damages a sum of money equal to all sums due and
     owing Landlord hereunder to said date, all reasonable costs and expenses
     incurred by Landlord as a result of Tenant's default, including reasonable
     attorneys' fees, the excess of the then present value of the Rent provided
     to be paid by Tenant for the balance of the Term over the fair market
     rental value (discounted to present value) of the Premises, after deduction
     of all anticipated expenses or reletting, for such period, and the
     unamortized portion of the Allowance given Tenant hereunder (assuming an
     amortization of such amount over the shortest period allowable under the
     Internal Revenue Code for the type of improvements installed in the
     Premises). In computing present value, a discount rate equal to the rate of
     interest on the most recently issued 10 Year U.S. Treasury bonds shall be
     used.  Should the fair market rental value of the Premises, after deduction
     of a reasonable estimate expenses of reletting, 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 of any part thereof; and

          (2)  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 or
     Tenant's obligation to pay Rent hereunder, in which event Landlord shall
     attempt to relet the same for the account of Tenant, for such rent and upon
     such terms as shall be reasonably satisfactory to Landlord.  For the
     purpose of such reletting, Landlord is authorized to decorate, repair,
     remodel or alter the Premises.  If Landlord shall fail to relet the
     Premises, Tenant shall pay to Landlord as damages a sum equal to the amount
     of the Rent reserved in this Lease for the balance of the Term, as and when
     payable pursuant to this Lease.  If the Premises are relet and a sufficient
     sum shall not be realized from such

                                     -32-
<PAGE>

     reletting after paying all of the reasonable costs and expenses of all
     decoration, repairs, remodeling, alterations and additions and the expenses
     of such reletting and of the collection of the rent accruing therefrom 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 Paragraph 23 from time to time and
     that no suit for 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 or otherwise recovered by
     Landlord.

          In the event Landlord defaults in the performance of any of its
obligations to Tenant hereunder, or breaches any representation, express or
implied, to Tenant in connection with this Lease, and such default or breach
continues for a period of thirty (30) days following written notice thereof from
Tenant to Landlord unless with respect to a default or breach which cannot be
cured within thirty (30) days, Landlord, in good faith, promptly after receipt
of such notice, shall have commenced and thereafter shall continue diligently to
reasonably prosecute and complete all action necessary to cure such default
within an additional forty-five (45) days, then Tenant may (i) take such action
as is reasonably necessary to cure Landlord's default, (ii) bring suit against
Landlord for damages, and/or (iii) bring suit to specifically enforce Landlord's
obligations under this Lease.  In the event Tenant cures such default by
Landlord as provided in item (i), Landlord will reimburse Tenant for all
reasonable costs and expenses incurred by Tenant in curing Landlord's default
within ten (10) days after notice from Tenant given from time to time as costs
are incurred. Notwithstanding the foregoing, in cases of emergency, Tenant may
cure Landlord's obligations if Landlord fails to commence the cure thereof as
soon as reasonably possible following Tenant's notice to Landlord.

     24.  EXPENSES OF ENFORCEMENT.
          -----------------------

          A.   Tenant shall pay upon demand all Landlord's reasonable costs,
charges and expenses, including the reasonable fees and out-of-pocket expenses
of counsel, agents and others retained by Landlord incurred in successfully
enforcing Tenant's obligations hereunder or incurred by Landlord in any
litigation, negotiation or transaction in which Tenant causes Landlord without
Landlord's fault to become involved or concerned.

          B.   Landlord shall pay upon demand all Tenant's reasonable costs,
charges and expenses, including the reasonable fees and out-of-pocket expenses
of counsel, agents and others retained by Tenant incurred in successfully
enforcing Landlord's obligations hereunder or incurred by Tenant in any
litigation, negotiation or transaction in which Landlord causes Tenant without
Tenant's fault to become involved or concerned.

     25.  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

                                     -33-
<PAGE>

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 and Landlord
shall defend, at Landlord's sole cost and expense, Tenant's right of quiet
enjoyment.

     26.  REAL ESTATE BROKER. Landlord and Tenant represent to each other that
          ------------------
neither has dealt with any real estate broker with respect to this Lease except
for LaSalle Partners Limited, which is a consultant to Tenant and is to be paid
by Tenant at its sole cost and expense, and The John Buck Company, which is a
consultant to Landlord and is to be paid by Landlord at its sole cost and
expense.  To each party's knowledge, except for the aforementioned brokers,  no
other broker initiated or participated in the negotiation of this Lease,
submitted or showed the Premises to Tenant or is entitled to any commission in
connection with this Lease, and each agrees to indemnify, defend and hold the
other harmless from all claims from any other real estate broker for commission
or fees in connection with this Lease claiming through such representing party.

     27.  MISCELLANEOUS.
          -------------

          A.   Building Name. Provided Tenant (including any Affiliate or
               -------------
Successor Entity) occupies at least 400,000 RSF in the Building and is not in
default hereunder (beyond any applicable cure period), the Building shall be
named "The Leo Burnett Building at 35 West Wacker Drive", and Tenant shall have
the sole right, from time to time, to change said name, subject to the written
approval of Landlord, which approval shall not unreasonably be  withheld or
delayed.

          B.   Approval of Tenants.   Provided Tenant is not in default
               -------------------
hereunder (beyond any applicable cure period) and so long as Tenant (including
any Affiliate or Successor Entity) shall occupy at least 400,000 RSF within the
Building, Tenant shall have the right to approve any lease first entered into
after the date hereof (excluding renewals or expansions of existing tenants) to
(i) any advertising agency (a "Restricted Tenant") and (ii) to any tenant in
which the name "Burnett" or any confusingly similar name is a part.  Such
approval may be arbitrarily withheld.  Landlord shall request such approval in
writing and if Tenant does not object in writing within ten (10) days of receipt
of Landlord's notice, then Tenant shall be deemed to have approved the proposed
lease. Notwithstanding the foregoing, Landlord may lease up to 25,000 RSF on one
(1) floor above the 34th floor of the Building to one (1) Restricted Tenant
without Tenant's approval, provided, however, that Landlord may not lease any
space in the Building to any of the following companies (including any firm,
person, corporation or entity now or hereafter controlling, controlled by or
under common control with said companies and such control is exercised via the
ability to direct or cause the direction of, the management and policies of the
other, whether through the ownership of voting securities, common directors or
officers, or otherwise) or any successor entity or any other party who succeeds
to a material portion of said companies' business which portion competes with
the business then being conducted by Tenant: (i) Interpublic Group Cos Inc.,
(ii) Omnicom Group Inc., (iii) True North Communications, (iv) Cordiant ADS, (v)
Grey Advertising, (vi) WPP Group, and (vii) Young & Rubicam.

                                     -34-
<PAGE>

          C.   Rights Cumulative.  All rights and remedies of Landlord and
               -----------------
Tenant under this Lease shall be cumulative, and none shall exclude any other
rights and remedies allowed by law.

          D.   Interest.  All payments becoming due under this Lease and
               --------
remaining unpaid when due shall bear interest until paid at the rate of two
percent per annum above the Prime Rate (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).

          E.   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.

          F.   Successors and Assigns.  Any reference in this Lease to Landlord
               ----------------------
or Tenant shall extend also to its respective successors and assigns, unless
expressly provided to the contrary. Each of the provisions of this Lease 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
Paragraph 27.F.  shall not permit any assignment by Tenant contrary to the
provisions of Paragraph 16 hereof.

          G.   Lease Contains All Terms.  All of the representations and
               ------------------------
obligations of Landlord and Tenant are contained herein and in the Exhibits
attached hereto, and 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 Landlord or Tenant, as the case may be, or by a duly
authorized agent of Landlord or Tenant, as the case may be, empowered by a
written authority signed by Landlord or Tenant, as the case may be.

          H.   Delivery for Examination.  Submission of the Lease for
               ------------------------
examination shall not bind either party in any manner, and no Lease or
obligations by either party shall arise until this instrument is signed by both
Landlord and Tenant and delivery is made to each.

          I.   Transfer of Landlord's Interest.  Tenant acknowledges that
               -------------------------------
Landlord and any of its successors and assigns may assign its interest in this
Lease to a mortgage lender as additional security on condition 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.  Notwithstanding aforesaid, Tenant agrees that the then Landlord
shall not be liable for any acts or omissions on the part of any successor,
assignee or transferee of Landlord after Landlord has made a bona fide
conveyance of ownership of the Land and Building.

          J.   Landlord's Title.  Landlord's title is and always shall be
               ----------------
paramount to the title of Tenant.  Nothing herein contained shall empower Tenant
to commit or engage in any act which can, shall or may encumber the title of
Landlord.

          K.   Recording.  This Lease may be recorded by Tenant, and Tenant may
               ---------
record a memorandum thereof in form and substance reasonably approved by
Landlord.

                                     -35-
<PAGE>

          L.   Captions.  The captions of Paragraphs and subparagraphs are for
               --------
convenience only and shall not be deemed to limit, construe, affect or alter the
meaning of such paragraphs or subparagraphs.

          M.   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.

          N.   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 reasonable discretion, may elect.

          O.   Time of Essence.  Time is of the essence of this Lease and each
               ---------------
of its provisions.

          P.   Governing Law.  Interpretation of this Lease shall be governed by
               -------------
the law of the State of Illinois.

          Q.   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 of 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.

          R.   Sculptures.  As long as Tenant (including any Affiliate and
               ----------
Successor Entity) occupies at least 400,000 RSF in the Building, Landlord hereby
agrees to keep all sculptures located in the Building lobby as of the date
hereof in the Building lobby.

     28.  LANDLORD'S SPECIAL COVENANTS.  Landlord covenants and agrees with
          ----------------------------
Tenant that:

          A.   Parking.  Tenant shall have the right to lease for the initial
               -------
fifteen (15) years of the Term up to 75 parking spaces in the Building's
underground garage at the rate of $250.00 per space, per month (inclusive of all
taxes), which amount shall not be subject to escalation; except that in addition
to, and concurrently with,  the payment of the foregoing $250 parking charge,
Tenant shall pay to Landlord for each of its parking spaces, the $30.00 per
month tax/fee imposed by the City of Chicago upon Landlord for each vehicle
parked in the garage.  Landlord and Tenant acknowledge and agree that Tenant
shall not be responsible for any increases to the foregoing City

                                     -36-
<PAGE>

of Chicago tax/fee or any new parking taxes or fees, but said $30.00 per month
tax/fee shall be reduced by the amount of any reduction, if any, to the
foregoing tax/fee levied by the City of Chicago. Such spaces shall be for the
exclusive use by Tenant and shall be in locations designated by Tenant, such
rights to extend through the term of this Lease and any extensions thereof, and
to include the right to sublease such spaces. In addition, Tenant shall be
entitled, at regular annual Building rates therefor, to any parking spaces which
were rented by the immediately preceding tenants in space added to the Premises
after the Commencement Date. Tenant may release such parking spaces, or any
thereof, so leased at any time(s) on not less than thirty (30) days' notice and
shall not have any rights for the number of spaces so released at any time
thereafter. Tenant may request additional parking spaces over and above the 75
space allocation which, subject to availability, shall be provided at the
monthly rate then prevailing in similar parking structures in downtown Chicago.
Landlord shall provide reduced parking rates for bikes and motorcycles
consistent with rates for bikes and motorcycles charged by similar parking
structures in downtown Chicago. Landlord shall continue to provide the amount,
type and quality of parking services which Landlord provides as of the date
hereof, including, but not limited to, car washes. If in the future Landlord
provides reserved parking spaces to other tenants in the Building, Landlord
shall also provide Tenant with the same right to have reserved parking as
provided to such other tenant.

     Landlord acknowledges that Tenant has a storage and workshop space on level
P-2 of the Building's parking garage (the "Storage and Workshop Space"), which
the parties acknowledge and agree contains approximately 1,500 RSF and occupies
six (6) parking spaces.  With respect to the Storage and Workshop Space, on or
before the Commencement Date, Tenant shall, in Tenant's sole discretion, either
(i) vacate the Storage and Workshop Space and remove all of Tenant's belongings
from the Storage and Workshop Space, (ii) elect to have the six (6) spaces of
the Storage and Workshop Space included as part of the aforementioned 75 parking
spaces allocated to Tenant or (iii) elect to lease the six (6) spaces of the
Storage and Workshop Space for the Term and to pay for such six (6) spaces at
the monthly rate for parking spaces charged by Landlord for spaces in the
Building's parking garage other than Tenant's 75 spaces.

          B.   Communication System.  Tenant shall have the right to maintain
               --------------------
any satellite, microwave, or other communication systems, if any, belonging to
Tenant and installed upon the Building's roof as of the Commencement Date
hereof.  In addition, Tenant shall have the right at any time during the Term
(or any extension thereof) to lease from Landlord up to 400 contiguous square
feet of additional space on the roof of the Building at no cost to Tenant for a
satellite, microwave or other communications system, so long as such system does
not impair the use by other tenants of their space in the Building or other
satellite, microwave or other communication systems then installed, or in
Landlord's reasonable judgment, compromise the aesthetics of the Building. Once
Tenant installs any of the foregoing systems, Landlord shall not enter into any
new agreements with any other tenants for the installation of  a satellite,
microwave or other communications system which impairs the use by Tenant of: (i)
its  space in the Building, or (ii) any satellite, microwave or other
communication systems then installed by Tenant.  Tenant shall submit plans for
such system and the names of the contractors who will be installing such system,
all of which shall be subject to Landlord's reasonable approval.  Tenant shall
pay all costs related to the installation, operation and maintenance of such
system, including without limitation, the cost of any structural modifications

                                     -37-
<PAGE>

to the Building made by Landlord and necessary, in the opinion of Landlord's
structural engineer, to accommodate the system.  Tenant shall, at Landlord's
option, remove any system(s) at the expiration of the Term, unless the Term is
extended, in which case Tenant shall, at Landlord's option, remove the system(s)
at the expiration of the Term as extended.  In each case, Tenant shall restore
the Building to the condition existing prior to the installation of any such
system(s).  Tenant shall secure all zoning and regulatory approvals necessary
for the system, at its expense.

          C.   Right of First Refusal for Roof Space. In addition to the above
               -------------------------------------
rights to rent space on the roof, Landlord hereby grants Tenant a right of first
refusal for any proposed leasing of space on the roof of the Building to any
other party.  At such time as Landlord desires to enter into a lease of any part
or portion of the space on the roof of the Building with a bona fide tenant,
Landlord shall give Tenant written notice of the terms and conditions of the
proposed lease.  Tenant shall have ten (10) business days from the receipt of
such notice to notify Landlord in writing that Tenant elects to lease said space
on the same terms and conditions as contained in Landlord's notice, and in such
case, Landlord and Tenant shall then enter into a lease of said space.  If
Tenant exercises this right, Tenant shall in fact use said roof space for
satellite, microwave or communications purposes.  In the event Tenant does not
exercise such election within said ten (10) day period, then Tenant shall be
deemed to have waived this right of first refusal for the proposed lease, but
such waiver shall be only for the lease proposed in Landlord's notice and not
for any subsequent proposed lease of space on the roof.  If the proposed lease
does not become effective within ninety (90) days after Landlord's notice, then
Tenant shall again have this right of first refusal with respect to that
proposed lease.  In no event shall Landlord allow any roof space to be used in a
manner that unreasonably interferes with Tenant's satellite, microwave or other
communications system on the roof.

          D.   Landlord's Alterations After Construction.  Other than as is
               -----------------------------------------
specifically allowed under the paragraphs of this Lease,  so long as Tenant
(including any Affiliate or Successor Entity) occupies at least 400,000 RSF of
the Building and is not in default hereunder (beyond any applicable cure
period), then the Landlord shall not, without in each case obtaining the prior
written consent of Tenant, construct, install or make any major alteration to,
or change in,  the exterior or facade of the Building, elevator lobby design or
signage, elevator cab upgrades, bathroom upgrades or corework, unless such major
alterations or changes are approved by Tenant, such approval not to be
unreasonably withheld or delayed.

     29.  NOTICES.  All notices to be given under this Lease shall be in writing
          -------
and delivered personally or deposited in the United States mail, certified or
registered mail with return receipt requested, postage prepaid, addressed as
follows:

          A.   If to Landlord, to:

               The John Buck Company
               233 South Wacker Drive
               Suite 550
               Chicago, Illinois  60606

                                      -38-
<PAGE>

               Attention:  President

               and to:

               Starwood Capital Group, L.P.
               Three Pickwick Plaza
               Suite 250
               Greenwich, Connecticut 06830
               Attention:  Madison Grose and Jonathan Eilian

or to such other person or such other address designated by notice sent by
Landlord to Tenant.

          B.   If to Tenant:

               Leo Burnett Company, Inc.
               35 West Wacker Drive
               Chicago, Illinois  60601
               Attention:  General Counsel



               with a copy (in the case of notice of default) to the attention
of:


               Kirkland & Ellis
               200 East Randolph Drive
               Chicago, Illinois 60601
               Attention: Stephen G. Tomlinson, Esq.

or to such other address as is designated by Tenant in a notice to Landlord.

          Notice by mail shall be deemed to have been given on the second
business day after deposit in the United States mail as aforesaid.

     30.  TENANT'S EXPANSION
          ------------------

          A.   Tenant shall have and is hereby granted the options to add the
 Expansion Space (hereinafter described in the following table), for the
 remaining Term of this Lease and any extensions thereof upon the same terms,
 covenants and conditions contained in this Lease, except for the payment of
 Base Rent (which shall be payable in the amounts described below) and except as
 otherwise specifically provided in this Paragraph 30. Tenant's obligation to
 pay Tenant's Expense Participation Amount, Base Rent and any other Rent or
 Additional Rent for any particular Expansion Space shall commence on the date
 such space is actually made available to Tenant to be added to

                                      -39-
<PAGE>

 the Premises. In the event that Tenant exercises its expansion option(s)
 pursuant to this Paragraph 30, the Expansion Space thereby added to the
 Premises shall become a part of the Premises for all purposes of this Lease,
 and any reference to the term "Premises" shall be deemed to refer to and
 include any such Expansion Space, except as otherwise expressly provided
 otherwise in this Lease.


<TABLE>
<CAPTION>
                                                                              (iv)
                                                      (iii)                 Base Rent
                                                 Period, based on           when such
                                                 anniversaries of             Space
                                                Commencement Date,           becomes
        (i)                 (ii)                within which Space           part of
       Space                                      becomes part                 the
       Called               Floor                of the Premises             Premises
-------------------  -------------------  ------------------------------ -------------------
<S>                  <C>                   <C>                            <C>
"First                    32nd floor        Six months before to             95% of
 Expansion              25,000 square       six months after 5th [2002]      "Market
 Space"                     feet            anniversary                      Rate"


 "Second                  38th floor        Six months before to             95% of
  Expansion             25,000 square       six months after 10th            "Market
  Space"                    feet            [2007] anniversary               Rate"
 </TABLE>


          B.   Tenant's options to expand shall be exercised as follows: On each
occasion, Landlord shall give Tenant notice of each particular Expansion Space,
the dates on which such spaces will be tendered to Tenant (the "Specification
Notice"), and the rent for such Expansion Space, not less than fifteen (15)
months prior to the earliest date stated in the Specification Notice for
delivery of any such Expansion Space (the "Availability Date"). Tenant shall
deliver a non-binding written notice to Landlord of its intent to exercise its
option to expand not less than thirteen (13) months prior to the Availability
Date of the Expansion Space (the "Option Notice"). If Tenant does not agree to
the rent specified in the Specification Notice, Tenant shall state in its Option
Notice that is desires the Market Rate to be calculated pursuant to Paragraph
30.G. Thereafter, the Market Rate for the particular Expansion Space will be so
calculated. Such calculation shall reflect the Market Rate that would be payable
per annum for a term commencing on the first day of the term for the particular
Expansion Space with respect to which the calculation is being made, provided
that such calculations shall be final and shall not be recalculated at the
actual commencement of such Expansion Space term (if any). If Tenant fails to
give its non-binding written notice of its intent to exercise its option to
expand when due as hereinabove provided, Tenant will be deemed to have waived
such option to expand.


                                      -40-
<PAGE>

          If Tenant exercises its expansion option,  Landlord shall deliver
possession of each particular Expansion Space to Tenant within a period
extending six (6) months prior to, until six (6) months after, the Availability
Date contained in the Specification Notice (the "Delivery Window").  Landlord
shall use reasonable efforts to deliver the Expansion Space to Tenant within the
Delivery Window and Landlord shall take all commercially reasonable actions to
remove holdover tenants from the Expansion Space.  Landlord acknowledges that
remedies at law will not be adequate for the damages Tenant will incur for a
failure by Landlord to deliver the Expansion Space within the Delivery Window.
Therefore, if Landlord fails to deliver the Expansion Space within the Delivery
Window, Tenant may pursue an action for specific performance.  In addition,
Landlord shall have the right, by notice to Tenant from time to time at least
six  (6) months prior to the then current Availability Date for any floor of any
Expansion Space, to change the location of such floor, provided that if the
floor or floors being replaced were to be contiguous to the Premises when added
to the Premises, the replacement floor or floors so designated must also be
contiguous to the Premises when added to the Premises.  Tenant's right to add
floors pursuant to these subparagraphs 30.A. and 30.B. shall be exercised in
full floor increments.

          C.   Each Expansion Space (or part thereof) shall become part of the
Premises and, except as provided in Paragraph 30.B., Tenant's rental obligation
for such Expansion Space (or part thereof) shall commence upon its delivery to
Tenant in accordance with Paragraphs 30.A. and 30.B.

          D.   Notwithstanding anything to the contrary contained herein, (i) if
Tenant exercises its first Contraction Option set forth in Paragraph 31 (i.e.
year 2000), Landlord may designate the Contraction Space set forth in the 2000
Contraction Option as the First Optional Expansion Space; and (ii) if Tenant
exercises its second Contraction Option set forth in Paragraph 31 (i.e. year
2005), Landlord may designate the Contraction Space set forth in such 2005
Contraction Option as the Second Optional Expansion Space. Landlord shall not
lease space of less than 3,000 RSF on any floor which is subject to any of
Tenant's expansion options without the prior written consent of Tenant, which
consent may be withheld in Tenant's sole discretion.

          E.   Tenant's notice of exercise of an option for Optional Expansion
Space or notice of exercise of any other rights or options granted pursuant to
Paragraphs 31, 32, 34 and 35 of this Lease shall be effective only if at the
time of service of such notice of exercise the following conditions (the
"Expansion Conditions") shall be satisfied:

          (1)  Landlord shall not have notified Tenant that Tenant is in default
     in the performance of any of the monetary or material non-monetary terms,
     covenants, and conditions contained in this Lease which default has not
     been cured;

          (2)  This Lease shall not have been terminated and shall be in full
     force and effect; and

          (3)  There shall not have been any assignment of Tenant's interest in
     this Lease except as provided in Paragraph 30.H.

                                      -41-
<PAGE>

          F.   The Base Rent for the First Expansion Space and Second Expansion
Space (as the case may be) shall be at a rate equal to 95% of the Market Rate
(defined hereinafter) for such space. For purposes of this Paragraph 30, "Market
                                                                          ------
Rate" shall mean the fair net rental per annum (which shall be net of all Taxes
----
and Operating Expenses) for a lease (but not a sublease) by a new tenant for
"comparable space" (hereinafter defined) for a period commencing when the fair
net rental being determined would first be payable, assuming no rent abatements
of any kind per rentable square foot, for a term equal to the number of years
remaining in the Term (including any Extension Term, with respect to which
Tenant has delivered its final binding written notice pursuant to Paragraph 34).
The calculation of Market Rate shall be calculated on a net present value basis
and shall take into account (and the fair net rental shall be decreased by the
present value of any then market brokers' commission and of any then market
tenant improvement, free rent other concession which would be available to a new
tenant, and shall also take into account (and the fair net rental shall be
increased by) the present value of the cost of any actual brokers' commission or
actual tenant improvement, free rent or other concession, if any, agreed by the
Landlord and Tenant to be payable or to be granted to Tenant in connection with
the particular expansion option with respect to which Tenant has given its non-
binding notice. The calculation of Market Rate shall also be based on the
assumption that there will be no financial escalation of Rent or stepping of
Rent or similar increases over time other than the 2.5% annual increase to Base
Rent provided for in Paragraph 4. The calculation of Market Rate shall also take
into account that Tenant pays Tenant's Proportionate Share of the Operating
Costs and Taxes in each fiscal year. As used herein, the term "comparable space"
means similar space in office buildings in the central business district of
Chicago where the Building is located, which are comparable to the Building in
reputation, quality, age, size, location, and level and quality of services
provided, and which have similar occupancy of the Building, but excluding those
leases where tenants have an equity interest in the building.

          G.   For purposes of Paragraphs 30 and 34 of this Lease "Market
Rate" shall be determined as follows:

          (1)  On or before five (5) days after the time at which Tenant must
     provide the Landlord with its non-binding written notice under this Lease
     of its intent to exercise any of its rights to: (i) expand the Premises
     under this Paragraph 30 or, (ii) extend the Term of this Lease under
     Paragraph 34, Landlord and Tenant shall commence negotiations to agree upon
     the Market Rate (to be multiplied by the RSF in the Premises) applicable
     thereto. If the Landlord and Tenant are unable to reach agreement on the
     Market Rate within twenty-one (21) days after the date negotiations
     commenced, then the Market Rate shall be determined in accordance with
     Paragraph 30.G.(2) below.

          (2)  If the Landlord and Tenant are unable to reach agreement on the
     Market Rate within said twenty-one (21) day period, then within seven (7)
     days, the Landlord and Tenant shall each simultaneously submit to each
     other in a sealed envelope its good faith estimate of the Market Rate
     (each, a "Good Faith Estimate"). If the higher of such estimates is not
     more than one hundred five percent (105%) of the lower of such estimates
     then the Market Rate shall be the average of the two estimates and shall be
     final and binding on Landlord and Tenant and Tenant's Option Notice shall
     become binding upon Tenant. Otherwise, within five (5) days after the
     expiration of such seven (7) day period Tenant may submit the question to
     arbitration in accordance with Paragraph 30.G.(3) below.

          (3)  If the Landlord and Tenant are unable to agree upon the Market
     Rate by exchange of Good Faith Estimates, then Tenant may, by written
     notice to Landlord within five (5) days after the exchange of Good Faith
     Estimates pursuant to Paragraph 30.G.(2) above, request to resolve the
     dispute by arbitration, whereupon Tenant's Option Notice shall become
     binding upon Tenant. If Tenant does not provide such notice within the

                                      -42-
<PAGE>

     aforementioned five (5) days, Tenant will be deemed to have waived its
     option to expand under this Paragraph 30 or its option to extend the Term
     of this Lease under Paragraph 34, as applicable. Within seven (7) days
     after the receipt of such request, the parties shall select, as an
     arbitrator, a mutually acceptable independent MAI appraiser with experience
     in real estate activities, including at least five (5) years experience in
     appraising office space in the central business district of the City of
     Chicago (a "Qualified Appraiser"). If the parties cannot agree on a
                 -------------------
     Qualified Appraiser, then within a second period of seven (7) days, each
     shall elect a Qualified Appraiser and within ten (10) days thereafter the
     two appointed Qualified Appraisers shall select a third Qualified Appraiser
     and the third Qualified Appraiser shall be the arbitrator and shall
     determine the Market Rate. If one party shall fail to make such appointment
     within said second seven (7) day period, then the Qualified Appraiser
     chosen by the other party shall be the sole arbitrator.

          (4)  Once the arbitrator has been selected as provided in Paragraph
     30.G.(3) above, then, as soon thereafter as practicable but in any case
     within twenty-one (21) days, the arbitrator shall select one of the two
     Good Faith Estimates of Market Rate previously submitted by the Landlord
     and Tenant in accordance with 30.G.(2) above, which shall be the one that
     is closer to the fair market net rental value as determined by the
     arbitrator. The value so selected shall be the Market Rate. The decision of
     the arbitrator as to the Market Rate shall be submitted in writing to, and
     be final and binding on, the Landlord and Tenant. If the arbitrator
     believes that expert advice would materially assist him, he may retain one
     or more qualified persons, including but not limited to, legal counsel,
     brokers, architects or engineers, to provide such expert advice. The party
     whose estimate is not chosen by the arbitrator shall pay the costs of the
     arbitrator and of any experts retained by the arbitrator. Any fees of any
     counsel or expert engaged directly by the Landlord or Tenant, however,
     shall be borne by the party obtaining such counsel or expert.

          H.   The provisions of this Paragraph 30 and Paragraphs 31, 32 and 34,
and 35 shall apply only to Tenant, and shall not inure to the benefit of any
assignee of Tenant other than (i) any party resulting from a merger or
consolidation with Tenant so long as Tenant or an Affiliate is the dominant and
controlling party after such merger, (ii) any party succeeding to the business
and assets of Tenant, or (iii) any Affiliate of Tenant.

          I.   Any space added to the Premises pursuant to this Paragraph 30
shall be delivered by Landlord to Tenant in broom clean condition, but otherwise
as is, and Landlord shall have no obligation to contribute to the cost of any
construction or remodeling by Tenant.

          J.   Promptly after Tenant's exercise of any expansion option,
Landlord shall prepare an amendment to the Lease, in a form reasonably
satisfactory to Landlord and Tenant, to reflect the increase to the size of the
Premises and Tenant's Proportionate Share and any other appropriate terms, due
to the exercise of such expansion option. Tenant shall execute and return such
an amendment to the Lease within fifteen (15) days after its submission to
Tenant.

     31.  CONTRACTION OPTION.  Tenant shall, provided that all the Expansion
          ------------------
Conditions are then satisfied, have the option (the "Contraction Option") to
                                                     ------------------
exclude from the Premises an area of one full floor of Premises designated by
Tenant as hereinafter provided, which contraction will be effective as of
February 28, 2000, 2005, and 2010 (the "Contraction Date"). Space designated by
                                        ----------------
Tenant to be excluded from the Premises (the "Contraction Space") must be at a
                                              -----------------
non-contiguous floor or the upper [or lower] end of the largest contiguous block
of space then leased by Tenant.

                                      -43-
<PAGE>

The Contraction Option shall be exercised, time being of the essence, by notice
given by Tenant to Landlord, on or before twelve (12) months prior to any such
Contraction Date identifying the Contraction Space (the "Contraction Notice").
                                                         ------------------
Each time Tenant fails to timely deliver its Contraction Notice, Tenant will be
deemed to have waived such Contraction Option for the applicable Lease year. If
Tenant timely delivers its Contraction Notice, then as of the relevant
Contraction Date: (i) Tenant shall vacate the Contraction Space and surrender
possession thereof to Landlord in accordance with the requirements of this
Lease; (ii) the Rentable Area of the Premises shall be reduced by the Rentable
Area of the Contraction Space so surrendered; and (iii) Tenant's Proportionate
Share shall be reduced by a percentage derived by dividing the Rentable Area of
the Contraction Space surrendered by the Rentable Area of the Office Portion of
the Building. If Tenant fails to completely vacate the Contraction Space and
surrender possession thereof to Landlord in accordance with Paragraph 17 of the
Lease on or before the Contraction Date, such failure shall be treated as a
holding over by Tenant, and Landlord shall be entitled to all of its remedies
thereof pursuant to Paragraph 18 of this Lease. Notwithstanding any such
vacation and surrender, Tenant shall remain liable for the payment to Landlord
of all rent and other sums due or accrued, and for the performance and keeping
of all the covenants, agreements and obligations under this Lease to be
performed, paid and kept by Tenant with respect to the Contraction Space prior
to the Contraction Date. Promptly after Tenant's exercise of its Contraction
Option, Landlord shall prepare an amendment to the Lease in a form reasonably
satisfactory to Landlord and Tenant to reflect the reduction to the size of the
Premises and Tenant's Proportionate Share and any other appropriate terms, due
to the return of the Contraction Space. Tenant shall execute and return such an
amendment to the Lease within fifteen (15) days after its submission to Tenant.

     32.  RIGHT OF FIRST REFUSAL. Provided Tenant (including any Affiliate or
          ----------------------
Successor Entity) occupies at least 400,000 RSF in the Building and is not in
default hereunder (beyond any applicable cure period), subject to Paragraph
32.B. below, and subject to any expansion, renewal, first offer, and first
refusal options of any current tenant(s) in the Building (individually, the
"Prior Tenant") during the Term of this Lease, Tenant shall, provided all
 ------------
Expansion Conditions are then satisfied, have and is hereby granted a right of
first refusal on any space in the Building of 5,000 RSF or more, that is not
originally demised to Tenant under this Lease (collectively, the "Refusal
                                                                  -------
Space"), which right shall be exercised in accordance with the procedures set
-----
forth in Paragraph 32.A. below.

          A.   If at any time during the Term of this Lease any Refusal Space
becomes available for lease to anyone other than a Prior Tenant, Landlord shall
give written notice thereof to Tenant ("Landlord's Refusal Notice"). Landlord's
                                        -------------------------
Refusal Notice must be given not less than six (6) months nor more than twelve
(12) months in advance of such availability and shall contain a summary of the
terms upon which Landlord intends to offer the Refusal Space for lease to the
market (the "Third Party Lease"). Landlord's Refusal Notice shall specifically
indicate the monthly payment stream (the "Monthly Payment"). The Monthly Payment
is a level monthly payment over the term of the Third Party Lease which, when
discounted at a monthly equivalent rate equal to a ten percent (10%) annual
rate, for the term of the Third Party Lease, equals the same net present value
as the economic terms (including, but not limited to, the net rental rate, free
rent period, tenant improvement allowances and leasing commissions) of the Third
Party Lease. Such Monthly Payment shall be the monthly rental rate for the
Refusal Space. Tenant shall notify Landlord in writing within fifteen (15) days
of receipt of Landlord's Refusal Notice whether it desires to lease the Refusal
Space on the terms set forth in Landlord's Refusal Notice; and failure to notify
Landlord within said fifteen (15) day period shall be deemed a refusal by
Tenant. After any such refusal or deemed refusal, Tenant shall have no further
rights to such Refusal Space and Landlord shall be free to lease such space to
any person or entity for any term, subject to Tenant's other options set forth
in this Lease and subject to the following conditions:

                                      -44-
<PAGE>

               (i)       The net present value as of the proposed commencement
     date of the Third Party Lease expressed as a single dollar figure,
     discounted using a rate of ten percent (10%) per annum, of all rent (other
     than such tenant's proportionate share of operating expenses and taxes) of
     whatever nature or however denominated for the term of the Third Party
     Lease less such net present value of all other proposed economic terms of
     the Third Party Lease shall not be less than ninety-five percent (95%) of
     the comparable amount determined by using the economic terms set forth in
     the Landlord's Refusal Notice for the space in question;

               (ii)      The Third Party Lease must be executed within six (6)
     months after the date of the Landlord's Refusal Notice; and

               (iii)     If a Third Party Lease does not meet the foregoing
     conditions, then Landlord shall not enter into the Third Party Lease until
     Landlord again complies with the provisions of this Paragraph 32 by
     delivering a new Landlord's Refusal Notice to Tenant and Tenant does not
     exercise its right of first refusal to lease such space on the terms and
     conditions set forth in the second Landlord's Refusal Notice within the
     applicable time periods.

Upon the expiration of the Third Party Lease, Tenant shall again have a right of
first refusal on the terms set forth in this Paragraph 32 with respect to the
space covered thereby.

          B.   If Tenant exercises its right of first refusal with respect to
such Refusal Space, such space shall be added to the Premises subject to the
following:

               (i)       If Tenant exercises its right of first refusal for a
     Refusal Space within the first ten (10) Calendar Years of the Term of the
     Lease, such Refusal Space shall be added to the Premises for the remaining
     Term of the Lease (including any exercised Extension Term(s)) on (i) all of
     the terms, covenants and conditions specified in Landlord's Refusal Notice
     (including, but not limited to, the Monthly Payment), and (ii) the terms,
     covenants and conditions of this Lease to the extent that such terms,
     covenants and conditions of this Lease do not conflict with Landlord's
     Refusal Notice;

               (ii)      If Tenant exercises its right of first refusal for a
     Refusal Space after the first ten (10) Calendar Years of the Term of the
     Lease, and such Refusal Space is less than 50,000 RSF, then such Refusal
     Space shall be added to the Premises for the remaining Term of the Lease
     (including any exercised Extension Term(s)) on (i) all of the terms,
     covenants and conditions specified in Landlord's Refusal Notice (including,
     but not limited to, the Monthly Payment), and (ii) the terms, covenants and
     conditions of this Lease to the extent that such terms, covenants and
     conditions of this Lease do not conflict with Landlord's Refusal Notice;

               (iii)     If Tenant exercises its right of first refusal for a
     Refusal Space after the first ten (10) Calendar Years of the Term of the
     Lease, and such Refusal Space is greater than 50,000 RSF, then such Refusal
     Space shall be added to the Premises for the term indicated in the
     Landlord's Refusal Notice, up to a maximum term of ten (10) years, on (i)
     all of the terms, covenants and conditions specified in Landlord's Refusal
     Notice (including, but not limited to, the Monthly Payment), and (ii) the
     terms, covenants and conditions of this Lease to the extent that such
     terms, covenants and conditions of this Lease do not conflict with
     Landlord's Refusal Notice.

                                      -45-
<PAGE>

provided, however, that notwithstanding anything contained herein to the
contrary during the Extension Terms, if any, rent and all other economic terms
applicable to any Refusal Space shall be adjusted in the manner provided in
Paragraph 34 hereof, and the rent and other economic terms described in
Landlord's Refusal Notice shall not apply in any Extension Term. Any Refusal
Space added to the Premises pursuant to this Paragraph 32.B. shall become a part
of the Premises for all purposes of this Lease, and any reference in this Lease
to the term "Premises" shall be deemed to refer to and include such portion of
the Refusal Space, except as expressly provided otherwise in this Lease.

          C.   Promptly after Tenant's exercise of its right of first refusal
pursuant to this Paragraph 32., Landlord shall prepare an amendment to the
Lease, in a form reasonably satisfactory to Landlord and Tenant, to reflect
changes in the size of the Premises, Base Rent, Tenant's Proportionate Share and
any other appropriate terms, due to the addition of the Refusal Space. Tenant
shall execute and return such an amendment to the Lease within fifteen (15) days
after its submission to Tenant.

     33.  LIMITATIONS ON LIABILITY; CONFIDENTIALITY..
          -----------------------------------------

          It is expressly understood and agreed by Tenant that none of
Landlord's covenants, undertakings or agreements are made or intended as
personal covenants, undertakings or agreements by Landlord, or its
beneficiaries, and any liability for damage or breach or nonperformance by
Landlord shall be collectible only out of Landlord's interest in the Building
and Land, if any, and no personal liability is assumed by, nor at any time may
be asserted against Landlord, its beneficiaries or any of their heirs, legal
representatives, successors and assigns, all such liabilities, if any, being
expressly waived and released by Tenant.

          Landlord further agrees, subject to the terms and provisions below,
and except as specifically set forth herein, to keep confidential any non-public
financial information of Tenant or its shareholders disclosed to Landlord under
the provisions of this Lease; provided, however, that nothing herein shall
restrict or prohibit disclosure of any such information: (a) that was or becomes
generally available to the public other than as a result of disclosure by
Landlord; (b) that was or becomes available on a non-confidential basis from a
source other than Tenant (provided that such source was not bound by a
confidentiality agreement with Tenant known to Landlord after reasonable
inquiries, if any, which a reasonable person under the circumstances would have
made); (c) to the extent required by statute, rule, regulation, law,
governmental authority or judicial process; (d) to any of the following: (i) any
entity which controls, is controlled by or is under common control with
Landlord; (ii) any successor of Landlord; and/or (iii) any actual or potential
purchaser, assignee or transferee of all or any portion of the Building; (e) in
connection with Landlord's administration of the Lease, to any of its examiners,
accountants, attorneys, consultants, appraisers, auditors or agents, to the
extent reasonably required; or (f) to any other person or entity to the extent
reasonably required in connection with any litigation, or proceeding to enforce
remedies under this Lease. Landlord shall require that those persons and
entities to whom disclosure is made pursuant to Paragraph 33(d) and (e), agree
                                                ---------------     ---
to be bound by the provisions of this Paragraph 33. In the event disclosure is
                                      ------------
required to be made pursuant to Paragraph 33(c), Landlord shall give Tenant
                                ---------------
notice thereof as promptly as practicable under the circumstances and Tenant
shall have the right to seek an appropriate protective order (the
"Confidentiality Requirements"). The provisions of this

                                      -46-
<PAGE>

Paragraph 33 shall supersede in their entirety all prior agreements and
------------
understandings concerning confidentiality or disclosure of information entered
into by Landlord and Tenant (or a parent, subsidiary of affiliate of either or
both of the foregoing) with respect to the matters set forth herein.

     34.  TENANT'S OPTIONS TO EXTEND.   Tenant shall, provided that all of the
          --------------------------
Expansion Conditions are then satisfied, have the right to extend the term of
this Lease for four additional periods of five (5) years each (each such period
is called an "Extension Term"). Each Extension Term shall be upon the same
              --------------
terms, covenants and conditions contained in this Lease, except the amount of
the annual Base Rent payable during any Extension Term, and any reference in the
Lease to the "Term" of the Lease shall be deemed to include any Extension Term
and apply thereto, unless it is expressly provided otherwise. Tenant shall have
no extension option beyond the aforesaid four consecutive five year extension
options. Any termination of this Lease during the initial Term of this Lease
shall terminate all rights under this Paragraph 34.

          A.   The Base Rent during an Extension Term for any space then
constituting a portion of the Premises (including, without limitation, any
Expansion Space) shall be at a rate equal to 95% of the "Market Rate". For
purposes of this Paragraph 34, "Market Rate" shall mean the fair net rental per
                                -----------
annum (which shall be net of all Taxes and Operating Expenses) for a period
commencing when the fair net rental being determined would first be payable,
assuming no rent abatements of any kind, per rentable square foot for an
existing tenant entering into any renewal lease for "comparable space"
(hereinafter defined), for a term equal to the Extension Term, but excluding any
renewal by an existing tenant at a rent agreed to at an earlier date pursuant to
a tenant's renewal option. The calculation of Market Rate shall be calculated
on a net present value basis and shall take into account (and the fair net
rental shall be increased by) the present value of the cost of any actual
brokers' commission or actual tenant improvement, free rent or other concession,
if any, agreed by the Landlord and Tenant to be payable or to be granted to
Tenant in connection with the particular extension option with respect to which
Tenant has given its non-binding notice). The calculation of Market Rate shall
also be based on the assumption that there will be no financial escalation of
Rent or stepping of Rent or similar increases over time. The calculation of
Market Rate shall also take into account that Tenant pays Tenant's Proportionate
Share of the Operating Costs and Taxes in each fiscal year. As used herein, the
term "comparable space" means similar size space in office buildings in the
central business district of Chicago where the Building is located, which are
comparable to the Building in reputation, quality, age, size, location, and
level and quality of services provided, and which have similar occupancy of the
Building, but excluding those leases where tenants have an equity interest in
the building.

          B.   Each option to extend shall be exercised by Tenant giving non-
binding notice to Landlord not later than eighteen (18) months prior to the end
of the initial Term (or 18 months prior to the end of the first, second, or
third extensions thereof, as the case may be), to extend the Term of this Lease
(the "Extension Notice"). Thereafter, the Market Rate for the particular
Extension Term shall be calculated pursuant to Paragraph 30.G. Such calculation
shall reflect the Market Rate that would be payable per annum for a term
commencing on the first day of the particular Extension Term with respect to
which the calculation is being made, provided that such recalculation shall be
final and shall not be recalculated at the actual commencement of such Extension
Term. If Tenant fails to timely give the Extension Notice, Tenant will be deemed
to have waived such option to extend. If Tenant fails to exercise any particular
option to extend set forth herein, then all subsequent options to extend the
Term shall expire.

     35.  RIGHT OF FIRST OFFER TO PURCHASE.
          --------------------------------

                                      -47-
<PAGE>

          A.   Right of First Offer.  Subject to and upon the terms and
               --------------------
conditions hereinafter set forth, Landlord hereby grants to Tenant the right of
first offer (herein sometimes called the "Right of First Offer") during the Term
                                          --------------------
(including any Extension Term) to purchase the Building and Land, or any portion
thereof or interest therein (herein referred to as the "Offered Property"), in
                                                        ----------------
the event Landlord elects, at any time during the Lease Term, to offer the
Offered Property for sale.  If, during the Lease Term, Landlord elects to offer
the Offered Property for Sale,  Landlord shall give written notice ("Notice of
                                                                     ---------
Offer") to Tenant setting forth the cash price at which Landlord intends to
-----
offer the Offered Property for sale, together with the other material terms and
conditions of such offer (herein called the "Offer").  Tenant shall have the
                                             -----
right, at its option, exercisable as hereinafter provided, to purchase the
Offered Property for the price and on the same terms and conditions set forth in
the Offer.

          B.   Exercise.  Provided that all the Expansion Conditions are then
               --------
satisfied, the Right of First Offer shall be exercised, if at all, by Tenant
giving written notice of exercise thereof (a "First Offer Notice") to Landlord
                                              ------------------
within 30 calendar days (the "First Offer Notice Period") after receipt by
                              -------------------------
Tenant of the Notice of Offer and pursuant to Paragraph 35.A. If Tenant provides
Landlord with a First Offer Notice, Tenant shall have three (3) months to close
under the terms of the Offer. If Tenant fails to close within such period, then
Tenant's Right of First Offer shall terminate.

          C.   Non-Exercise.  In the event Tenant does not timely exercise its
               ------------
Right of First Offer with respect to any Notice of Offer, Landlord shall have
six (6) months to market the Offered Property covered by the subject Offer to
any third party who is willing to purchase the Offered Property in accordance
with such Offer. If no contract is executed within said six (6) month period,
Tenant's Right of First Offer with respect to the Offered Property shall be
reinstated. Should Landlord materially change the economic or financial terms of
the Offer presented to Tenant, or enter into a contract or contract amendment
which materially changes the economic or financial terms of the Offer presented
to Tenant, then such modified or amended Offer or contract, as the case may be,
shall constitute a new Offer hereunder and Tenant's Right of First Offer shall
apply thereto, obligating Landlord to present such new Offer to Tenant and
entitling Tenant the right to exercise the Right of First Offer as to such new
Offer in the manner hereinbefore provided. For the purposes of this Paragraph
35.C., a "material" change in the economic terms of the Offer shall mean a
change in the total economic terms of the Offer of greater than or equal to 3%.
In the event of any sale to a third party in accordance with the requirements of
this Paragraph 35, upon the closing of such purchase this Right of First Offer
shall be deemed to automatically expire with respect to the Offered Property and
Tenant, at Landlord's request, shall promptly execute and deliver to Landlord an
instrument releasing and quitclaiming any and all interest Tenant would
otherwise have under this Paragraph 35 to the purchaser of the Offered Property.

          D.   Third Party Offers.  Any offer made by a third party to Landlord
               ------------------
for the purchase of the Offered Property, other than in lieu of condemnation,
shall give Tenant the same rights under this Paragraph 35 as if such offer were
an offer made by Landlord for the sale of the Offered Property.

          E.   Exceptions to Right of First Offer. Tenant's Right of First Offer
               ----------------------------------
shall not apply to: (a) any Offered Property acquired by a third party in a
condemnation proceeding or a conveyance in lieu of condemnation; (b) any
conveyance resulting from the foreclosure of a mortgage or other instrument
encumbering the Offered Property, or any deed (or transfer or other form of
conveyance or assignment) given or made in lieu of such foreclosure; (c) any
transfer by a partnership to any of its partners; (d) any transfer between or
among partners; (e) any transfer to an affiliate of Landlord. As used herein the
term "affiliate" means any equity holder of the transferring entity, any
corporation or entity owned or controlled, directly or indirectly, by the
transferring entity.

                                     -48-
<PAGE>

     36.  CONSENTS.  Whenever under any terms or provisions of this Lease
          --------
either party's consent or approval is required or requested or performance by
either party of any act or other matter or thing is to be to the satisfaction of
or acceptable to the other party, such consent or approval shall not be
unreasonably withheld or delayed and such party shall not be unreasonable in
withholding its satisfaction or acceptance, always excepting any instance where
it is provided that such party may act arbitrarily or at its discretion and any
instance in which specific standards for consent or approval are provided in
this Lease.

     37.  TAX CONSEQUENCE OFFSET.  Pursuant to the Contribution Agreement and
          ----------------------
the terms of that certain Amended and Restated Limited Liability Company
Agreement for 35 W. Wacker Venture L.L.C. (the "Venture Agreement"), dated of
even date hereof, Landlord has agreed to comply with the Transfer Prohibition
(as defined in the Venture Agreement) and to maintain a level of non-recourse
debt against the Building and the Land sufficient to avoid any adverse tax
consequences to Tenant throughout the Restrictive Period (as defined in the
Venture Agreement). Pursuant to Section 25 of the Venture Agreement, Landlord
has agreed to indemnify Tenant against (i) any violations of the Transfer
Prohibition and (ii) Landlord's failure to comply with the aforementioned debt
maintenance requirement.  In order to secure Landlord's  indemnity obligations
under Section 25 of the Venture Agreement, Landlord and Tenant hereby
acknowledge and agree that Tenant shall be permitted to offset against Rent
accruing under this Lease if Landlord fails to make any payments in respect of
amounts due under the indemnification provisions of Section 25 of the Venture
Agreement, an amount equal to the indemnification payments to have been made
under said Section 25.  Such offset shall be made against Rent next becoming due
under this Lease until the offset is fully exhausted.  Notwithstanding the
foregoing, such offset shall be limited to a maximum of $9,200,000.00.

     38.  FINANCIAL INFORMATION.  During each Calendar Year of the Term of this
          ---------------------
Lease, upon not less than thirty (30) nor more than sixty (60) days written
notice from Landlord to Tenant, Landlord and Landlord's lender may review
Tenant's audited financial statements for the then most recent Calendar Year (to
the extent available) at the Premises and under Tenant's supervision (the
"Financial Review"). Except as provided below, Landlord and Landlord's lender
shall not perform a Financial Review more than once per Calendar Year (the
"Annual Financial Review") during the Term hereof and Landlord and Landlord's
lender shall not be entitled to copies of such audited financial statements or
any supporting documentation. Each Annual Financial Review shall be subject to
the Confidentiality Requirements set forth in Paragraph 33 herein. In addition
to the Annual Financial Review, Landlord shall have a one time right to conduct
a Financial Review, subject to the Confidentiality Requirements, under each of
the following circumstances: (i) with the lead underwriter who is managing the
underwriting of securities to be offered in connection with the transfer of the
ownership interests in the Landlord or the Property to a real estate investment
trust or partnership controlled by a real estate investment trust pursuant to
the terms of the Venture Agreement; and (ii) following the expiration of the
Restrictive Period, with the purchaser or a representative of the purchaser in
connection with the sale of the Building after the Restrictive Period. If
Landlord foregoes its Annual Financial Review for any Calendar Year, Landlord
shall

                                     -49-
<PAGE>

also have the one time right in that Calendar Year to conduct a Financial
Review, subject to the Confidentiality Requirements, under either circumstance
(i) or circumstance (ii) above.

                                     -50-
<PAGE>

     IN WITNESS WHEREOF, the parties hereto have executed this Lease as of the
date first above written.

               LANDLORD:            35 W. WACKER VENTURE L.L.C.

                                    By:_________________________

                                    Name:_______________________

                                    Title:______________________


               TENANT:              LEO BURNETT COMPANY, INC., a
                                    Delaware corporation

                                    By:_________________________

                                    Name:_______________________

                                    Title:______________________

                                     -51-
<PAGE>

                                   EXHIBIT A

                      LEGAL DESCRIPTION OF REAL PROPERTY
                      ----------------------------------


     LOTS 1, 3 AND 4  IN THE LEO BURNETT RESUBDIVISION OF A TRACT OF LAND IN THE
EAST HALF OF THE SOUTHEAST QUARTER OF SECTION 9, TOWNSHIP 39 NORTH, RANGE 14,
EAST OF THE THIRD PRINCIPAL MERIDIAN, ACCORDING TO THE PLAT THEREOF RECORDED
MARCH 15, 1990 AS DOCUMENT NUMBER 90117214, IN COOK COUNTY, ILLINOIS.









P.I.N.:  LOT 1  17-09-426-030
                LOT 3  17-09-426-032
                LOT 4  17-09-426-033

(Common Street Address 35 W. Wacker Drive, Chicago, Illinois)
<PAGE>

                                   EXHIBIT B

                                    BR/RSF
                                      ||

 Lease Year    Effective       Lease      End Month   BR/RSF
 ----------    ---------    Anniversary   ---------   ------
                            -----------
--------------------------------------------------------------------------------
    1                            0           12     $14.55
--------------------------------------------------------------------------------
    2                            1           24     $14.91
--------------------------------------------------------------------------------
    3                            2           36     $15.29
--------------------------------------------------------------------------------
    4                            3           48     $15.67
--------------------------------------------------------------------------------
    5                            4           60     $16.06
--------------------------------------------------------------------------------
    6                            5           72     $16.46
--------------------------------------------------------------------------------
    7                            6           84     $16.87
--------------------------------------------------------------------------------
    8                            7           96     $17.30
--------------------------------------------------------------------------------
    9                            8          108     $17.73
--------------------------------------------------------------------------------
   10                            9          120     $18.17
--------------------------------------------------------------------------------
   11                           10          132     $18.63
--------------------------------------------------------------------------------
   12                           11          144     $19.09
--------------------------------------------------------------------------------
   13                           12          156     $19.57
--------------------------------------------------------------------------------
   14                           13          168     $20.06
--------------------------------------------------------------------------------
   15                           14          180     $20.56  End of Initial Term
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
                                      ||
<PAGE>

                                   EXHIBIT C

                             35 WEST WACKER DRIVE
                               CHICAGO, ILLINOIS

                        BUILDING PERFORMANCE STANDARDS
<PAGE>

                                   EXHIBIT D

                             35 WEST WACKER DRIVE
                               CHICAGO, ILLINOIS

                              JANITORIAL SERVICES


I.   NIGHTLY - Monday through Friday (Holidays Excluded)

     A.   Dust mop, using a treated mop, all stone, ceramic tile, terrazzo and
          other types of unwaxed flooring.

     B.   Dust mop, using a treated mop, all vinyl, asbestos, asphalt, rubber
          and similar types of flooring. This includes removal of gum and other
          similar substances using a scraping device.

     C.   Vacuum all carpeted areas.

     D.   Dust mop all private and public stairways and vacuum if carpeted.

     E.   Hand dust and wipe clean with a chemically treated cloth all
          furniture, file cabinets, fixtures, window sills (do not disturb
          papers on desks).

     F.   Dust and sanitize, using a disinfectant solution, all telephones.

     G.   Remove finger marks from all painted surfaces near light switches,
          entrance doors, etc.

     H.   Remove all gum and foreign matter on sight.

     I.   Empty and clean all waste receptacles and remove waste paper and waste
          materials to a designated area.

     J.   Damp dust interiors of all waste disposal receptacles and wash as
          necessary.

     K.   Clean and sanitize, using a disinfectant solution, all water fountains
          and water coolers.

     L.   Spot mop floors for spillages, etc.

     M.   Empty and damp clean all ash trays and screen all sand urns.

     N.   Remove finger marks and dust doors of elevator hatchways.
<PAGE>

     O.   Clean all low ledges, shelves, bookcases, etc., that are in office
          spaces.

     P.   Upon completion of work, all slop sinks are to be thoroughly cleaned
          and cleaning equipment and supplies stored neatly in locations
          designated by Building Manager's Office.

     Q.   All cleaning operations shall be scheduled so that a minimum of lights
          are to be left on at all times.  Upon completion of cleaning, all
          lights are to be turned off.  All entrance doors are to be kept locked
          during the cleaning operation.

     R.   Sweep all steps, sidewalks and plazas.

     S.   Clean elevator cabs, including floors.

     T.   Sweep clean loading dock areas.

     U.   In building lobby, dust and wipe clean mail chutes, mail depository
          door glass, metal door knobs, kick plates, and directional signs.

II.  WEEKLY

     A.   Hand dust all door louvers and other ventilating louvers within reach.

     B.   Dust all baseboards.

     C.   Wipe clean all bright work.

     D.   Dust all chair rails.

     E.   Move and vacuum clean once a week underneath all furniture that can be
          moved.

     F.   In high traffic resilient tile areas, damp mop if necessary and apply
          spray buffing solution in a fine mist and buff with a synthetic pad.

     G.   Damp mop all non-carpeted private and public stairways.

     H.   Wipe clean all interior building metals.

     I.   Clean building directory glass.

     J.   Wash all glass entrance doors and side panels inside and out.

     K.   Hose down loading dock areas.
<PAGE>

     L.   Wash entrance lobby walls.

     M.   Sweep clean garage.

III. MONTHLY

     A.   Dust entrance fixtures and other fittings in public corridors. Replace
          bulbs with contractor supplies.

     B.   Shampoo common area and elevator carpeting. Thoroughly scrub resilient
          tile floors in all public areas.

     C.   When possible, sweep and hose down exterior walks, trucking areas and
          shipping platforms.

     D.   Scrub down loading dock area.

     E.   Dust all picture frames, charts and venetian blinds which are not
          reached in nightly cleaning.

IV.  QUARTERLY

     A.   Dust all vertical surfaces such as walls, partitions, doors and other
          surfaces not reached in nightly cleaning.

     B.   Dust exterior of lighting fixtures.

     C.   Dust all air-conditioning louvers, grills, etc.

     D.   Wash all baseboards.

     E.   Strip all resilient flooring using diluted stripping solution. Machine
          scrub floor using pad to remove all floor finish. Thoroughly rinse
          with clean water and apply two coats of floor finish.

     F.   Vacuum upholstered furniture.

V.   LAVATORIES

     A.   Nightly - Monday - Friday

          (1)  Clean, sanitize using disinfectant solution and polish all
               vitreous fixtures including toilet bowls, urinals and wash
               basins.
<PAGE>

          (2)  Clean and polish all chrome and stainless steel fittings.

          (3)  Clean and sanitize both sides of toilet seats.

          (4)  Clean and polish all glass and mirrors.

          (5)  Empty all containers and disposals and insert new liners where
               required.

          (6)  Wash and sanitize using a disinfectant solution, exteriors of all
               containers.

          (7)  Empty all sanitary containers and sanitize interiors using a
               disinfectant solution.

          (8)  Dust horizontal surfaces of all partitions.

          (9)  Spot clean all partitions and remove all graffiti.

          (10) Spot clean all walls, doors, light switches, etc.

          (11) Refill all dispensers to normal limits including napkins, soap,
               tissue, towels, etc.

          (12) Wet mop and sanitize tile floors.

          (13) Vacuum entire carpeted areas.

          (14) Remove all rubbish.

          (15) Wet mop tile floors.

     B.   BI-WEEKLY

          (1)  Wash partitions.

     C.   MONTHLY

          (1)  Wash partitions.

     D.   QUARTERLY

          (1)  Dust all HVAC grills and louvers.

          (2)  Wash ceramic tile walls.
<PAGE>

VI.  MISCELLANEOUS

     A.   Cleaning of computer rooms and kitchens will be the sole
          responsibility of the tenant.

     B.   Remove snow and ice from parking entrances, sidewalks and roadways
          servicing the property.

     C.   Sidewalk, entrances including dock and grounds to be kept clean of
          paper, leaves and debris.

     D.   Put out in lobby floor mats during inclement weather and clean floor
          mats as necessary.

     E.   Keep escalators, if any, in clean and polished condition.

     F.   Keep walls and ceiling clean.
<PAGE>

                                   EXHIBIT E

                             35 WEST WACKER DRIVE
                               CHICAGO, ILLINOIS

                             RULES AND REGULATIONS

     RULES AND REGULATIONS.  Tenant agrees to observe the rights reserved to
Landlord in the Lease and agrees, for itself, its employees, agents, clients,
costumers, invitees and guests, to comply with the following rules and
regulations with such reasonable modifications thereof and additions thereto as
Landlord may make, from time to time, for the Building.

     (a)  Except as provided in the Lease, any sign, lettering, picture, notice,
or advertisement installed within Tenant's Premises which is visible to the
public from within the Building shall be installed at Tenant's cost and in such
manner, character and style as Landlord may approve in writing such approval not
to be unreasonably withheld.

     (b)  Tenant may use the address of the Building as its business address for
any reasonable business purpose.

     (c)  Tenant, its customers, invitees, licensees, and guests shall not
obstruct sidewalks, entrances, passages, courts, corridors, vestibules, halls,
elevators and stairways in and about the Building.  Tenant shall not place
objects against glass partitions or doors or windows or adjacent to any open
common space which would be unsightly from the Building corridors or from the
exterior of the Building, and will promptly remove the same upon notice from
Landlord.

     (d)  Tenant shall not make excessive noises, cause disturbances, create
excessive vibrations, odors or noxious fumes or use or operate any electrical or
electronic devices or other devices that emit excessive sound waves or are
dangerous to other tenants and occupants of the Building or that would
materially interfere with the operation of any device or equipment or radio or
television broadcasting or reception from or within the Building or elsewhere,
and shall not place or install any projections, antennae, aerials or similar
devices outside of the Premises except as provided in the Lease.

     (e)  Tenant shall not make any room-to-room canvas to solicit business from
other tenants in the Building, and shall not exhibit, sell or offer to sell,
use, rent or exchange any item or services in or from the Premises unless
ordinarily embraced within the Tenant's use of the Premises as specified in its
value.

     (f)  Tenant shall not waste electricity or water and agrees to cooperate
fully with Landlord to assure the most effective operation of the Building's
heating and air-conditioning and shall refrain from attempting to adjust any
controls except for the thermostats within the Premises. Tenant shall keep
public corridor doors closed.
<PAGE>

     (g)  Door keys for doors in the Premises will be furnished at the
commencement of the Lease by Landlord.  Tenant shall not affix additional locks
on doors and shall purchase duplicate keys only from Landlord.  When the Lease
is terminated, Tenant shall return all keys to Landlord and will provide to
Landlord the means of opening any safes, cabinets or vaults left in the
Premises.

     (h) Tenant assumes full responsibility for protecting its space from theft,
robbery and pilferage.  Tenant's responsibility includes keeping doors locked
and other means of entry to the Premises closed and secured.

     (i)  Peddlers, solicitors and beggars shall be reported to the office of
the Building or as Landlord otherwise requests.

     (j)  Tenant shall neither install nor operate machinery or any mechanical
devices of a nature not directly related to Tenant's ordinary use of the
Premises without the written permission of the Landlord, which permission shall
not be unreasonably withheld.

     (k)  Tenant shall not:

          (1)  Use the Premises for lodging or for any immoral or illegal
               purposes;

          (2)  Use the Premises to engage in the manufacture or sale of any
               spirituous, fermented, intoxicating or alcoholic beverages;

          (3)  Use the Premises to engage in the manufacture or sale of, or
               permit the use of, any illegal drugs on the Premises.

     (l)  In no event shall any person bring into the Building inflammables such
as gasoline, kerosene, naphtha and benzene, or explosives or firearms or any
other article of intrinsically dangerous nature.  If for any reason of the
failure of Tenant to comply with the provisions of this paragraph, any insurance
premium payable by Landlord for all or any part of the Building shall at any
time be increased above normal insurance premiums for insurance not covering the
items aforesaid, Landlord shall notify Tenant and following a reasonable cure
period have the option to require Tenant to make payment for the whole of the
increased insurance premium within thirty (30) days after notice to Tenant.

     (m)  Tenant shall comply with all applicable federal, state and municipal
laws, ordinances and regulations and building rules, and shall not directly or
indirectly make any use of the Premises which may be prohibited thereby or which
shall be dangerous to person or property or shall increase the cost of insurance
or require additional insurance coverage.

     (n)  If Tenant desires signal, communication, alarm or other utility or
service connection installed or changed, the same shall be made at the expense
of Tenant, with reasonable approval and under direction of Landlord.
<PAGE>

     (o)  Bicycles shall not be permitted in the Building in other than
Landlord-designated locations.

     (p)  Tenant shall cooperate and participate in all reasonable security
programs affecting the Building.

     (q)  Tenant, its customers, invitees, licensees, and guests shall not
loiter, eat, drink, sit or lie in the lobby, plaza or other spaces in the
Building or the adjacent property owned by the landlord which are open to the
public.

     (r)  Tenant shall not, and Tenant shall not permit or suffer anyone to
allow any pets in the Premises.

     (s)  Tenants shall not use any draperies or other window coverings instead
of or in addition to the building standard window coverings designated and
approved by Landlord for exclusive use throughout the Building.

     (t)  Tenant, its customers, invitees, licensees, and guests shall not use
the freight or passenger elevators of the Building except in accordance with the
reasonable regulations for the use established by Landlord.

     (u)  In the event Landlord allows one or more tenants in the Building to do
any act prohibited herein, Landlord shall not be precluded from denying any
other tenant the right to do any such act.

     (v)  In the event of a conflict between the terms of these rules and
regulations and the terms of the Lease, the terms of the Lease shall control.