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                                                                   Exhibit 10.26


                         FIRST AMENDMENT TO 1501 LEASE
                         -----------------------------

    THIS AMENDMENT, made as of the 1st day of November, 1997, between BANK ONE,
ILLINOIS, N.A., not personally but solely as Trustee under Trust Agreement dated
May 23, 1997, and known as Trust No. 11097 ("Landlord") and MAY & SPEH, INC.
("Tenant").

                                   RECITALS

     Landlord and Tenant are parties to a written lease dated June 2, 1997,
("1501 Lease"), for the entire building ("1501 Building") located at 1501 Opus
Place, Downers Grove, Illinois. Section S.4 of the 1501 Lease grants Tenant
certain options to acquire the 1501 Building and the land thereunder; provided
that, Tenant also exercises the option to purchase the building ("3333
Building") to be constructed by Landlord and leased to Tenant on the land
commonly referred to as 3333 Finley Road, Downers Grove, Illinois pursuant to
the option granted in the lease between Landlord and Tenant also dated June 2,
1997 for the 3333 Building ("3333 Lease").

    The terms and conditions of Tenant's option to purchase the 1501 Building
are set forth in Rider E to the 1501 Lease and the terms and conditions of the
purchase of the 3333 Building are set forth in Rider E to the 3333 Lease. The
purchase price for the 1501 Building is set forth in Rider E to the 1501 Lease
and the purchase price for the 3333 Building is based on a formula which takes
into account the purchase price for the 1501 Building. Landlord and Tenant
desire to increase the purchase price for the 1501 Building and to make a
similar reduction to the purchase price of the 3333 Building to permit Landlord
to refinance the 1501 Building and to finance the construction of the 3333
Building. Landlord and Tenant have also agreed that Tenant will assume any
financing on the respective buildings if it exercises its option to purchase.

    Landlord and Tenant have agreed to modify the Base Building Improvements
under the 3333 Lease to include the construction of a tunnel ("Tunnel") from the
1501 Building to the 3333 Building and modify the Maximum Project Costs to take
into account the change in the Base Building Improvements. The portion of the
Tunnel on the Land is to be included in the Premises.

    Tenant is also constructing an approximate 15,000 square foot addition to
the Building for use as storage space ("Storage Addition").

          NOW, THEREFORE, in consideration of the mutual covenants and
conditions contained herein, the Lease is hereby amended as follows:

     1.   All capitalized terms used herein shall have the same meanings as in
the 1501 Lease unless otherwise defined herein.

    2.    Notwithstanding anything in the 1501 Lease to the contrary, the
Premises shall include the portion of the Tunnel located on the Land and the
Storage Addition and Tenant's obligations under this Lease with respect to the
Premises, including without limitation, its obligations to maintain and repair
the Premises, shall apply to the portion of the Tunnel included in the Premises
and the Storage Addition.
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     3.   Section 3.1 of the Purchase Contract attached as Rider E to the 1501
Lease is amended in its entirety to read as follows:

                 3.1 PURCHASE PRICE. The purchase price ("Purchase Price") for
       the Property shall be Twelve Million Eight Hundred Thousand and 00/100
       Dollars ($12,800,000.00).

          Purchaser agrees to pay to Seller and Seller agrees to accept payment
       of the Purchase Price as follows:

                 (a) At Closing, Purchaser shall accept title to the Property
       subject to the lien of the First Mortgage (which Purchaser or its nominee
       or designee will take subject to, and with respect to which First
       Mortgage and the loan evidenced and secured thereby Purchaser or its
       nominee or designee shall assume), and the outstanding principal balance
       thereunder shall be credited against the Purchase Price.

                 (b) The remaining portion of the Purchase Price, subject to
       prorations and adjustments as provided in Section 8.1, shall be paid on
       the Closing Date by wire transfer of immediately available funds, first
       to the Title Company and then to an account specified by Seller, against
       delivery of instruments of transfer and the other documents specified in
       Section 7.1.

     4.   Except for the provisions of this Amendment, all the terms, covenants,
and conditions of the Lease and all the rights and obligations of Landlord and
Tenant thereunder, shall remain in full force and effect, and are not otherwise
altered, amended, revised or changed.

     5.   It is understood and agreed expressly by and between the parties
hereto, anything herein to the contrary notwithstanding, that each and all of
the representations, warranties, covenants, undertakings and agreements made
herein on the part of Landlord, while in form purporting to be the
representations, warranties, covenants, undertakings and agreements of Landlord,
are nevertheless each and every one of them made and intended, not as personal
representations, warranties, covenants, undertakings and agreements by Landlord
or for the purpose or with the intention of binding Landlord personally, but are
made and intended for the purpose only of subjecting Landlord's interest in the
Building, the Land and the Premises to the terms of this Lease and for no other
purpose whatsoever, and in case of default hereunder by Landlord (or default
through, under or by any of its beneficiaries, or agents or representatives of
said beneficiaries), Tenant shall look solely to the interests of Landlord in
the Building and Land; that this Lease is executed and delivered by Landlord not
in its own right, but solely in the exercise of the powers conferred upon it as
trustee; that neither Landlord nor any of Landlord's beneficiaries shall have
any personal liability to pay any indebtedness accruing hereunder or to perform
any covenant, either express or implied, contained herein and no liability or
duty shall rest upon Landlord to sequester the trust estate or the rents, issues
and profits arising therefrom, or the proceeds arising from any sale or other
disposition thereof; and that no personal liability or personal responsibility
of any sort is assumed by, nor at any time shall be asserted or enforceable
against, said Landlord, individually

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or personally, but only as trustee under the provisions of the trust agreement
establishing the trust, or against any of the beneficiaries under the trust
agreement establishing the trust on account of this Lease or on account of any
representation, warranty, covenant, undertaking or agreement of Landlord
contained in this Lease, either express or implied, all such personal liability,
if any, being expressly waived and released by Tenant and by all persons
claiming by, through or under Tenant.

     IN WITNESS WHEREOF, the parties have caused this Amendment to be executed
on the date first above written.

                                       LANDLORD:

                                       BANK ONE, ILLINOIS, NA, not personally,
                                       but as Trustee aforesaid

                                       RIDER ATTACHED HERETO IS HEREBY 
                                       EXPRESSLY MADE A PART HEREOF.

                                       By:
                                           ------------------------------------
                                       Its:
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                                       TENANT:

                                       MAY & SPEH, INC.


                                       By: /s/ 
                                           ------------------------------------
                                       Its: CFO
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