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                                                                    EXHIBIT 10.2

 
                     FIRST AMENDMENT TO SECURITY AGREEMENT



          This First Amendment to Security Agreement, dated as of January 30,
1998 made by May & Speh, Inc., an Illinois corporation (the "Borrower"), to The
Northern Trust Company, in its capacity as collateral agent (the "Agent") to the
Lenders referred in the Security Agreement (defined below).

          WHEREAS, the Borrower and the Agent are parties to that certain
Amended and Restated Security Agreement dated as of May 16, 1994 (the "Security
Agreement"); and

          WHEREAS, the Borrower has requested the Agent, and the Agent on behalf
of the Lenders has agreed, to release the lien on certain assets of the
Borrower;

          NOW THEREFORE, in consideration of the foregoing and other good and
valuable considerations, the parties hereby agree as follows:

          1. Amendment to Security Agreement. The Security Agreement is hereby
             amended by deleting Section 1 thereof in its entirety and
             substituting the following in lieu thereof:

             "1.  Grant of Security Interest. The Borrower hereby grants to the
             Agent for the benefit of the Lenders to secure the payment of all
             monies due by the Borrower to the Lenders and the performance of
             all obligations of the Borrower to the Lenders under the Northern
             Loan Agreement, under any note issued from time to time in
             connection with the Northern Loan Agreement, under the Harris Note
             and under all other documents and agreements delivered pursuant to
             the Northern Loan Agreement or the Harris Note (collectively, the
             "Loan Documents"), of every kind and description whether absolute
             or contingent, due or to become due, now existing or hereafter
             incurred (collectively, the "Obligations"), a security interest in
             the following assets of the Borrower (the "Collateral"): (a) the
             ESOP Note and the Pledged Shares; and (b) all additions,
             replacements, substitutions, accessions, proceeds and products of
             the foregoing."

          2. No Other Amendment. Except for the amendment expressly set forth
above, the text of the Security Agreement and all other Loan Documents shall
remain unchanged and in full force and effect. The Borrower acknowledges and
expressly agrees that

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the Lenders reserve the right to, and do in fact, require strict compliance with
all terms and provisions of the Security Agreement and the other Loan Documents.

          3.   Governing Law. This Amendment shall be deemed to be made pursuant
to the laws of the State of Illinois with respect to agreements made and to be
performed wholly in the State of Illinois, and shall be construed, interpreted,
performed and enforced in accordance therewith.

          4.   Definitions. All capitalized terms not otherwise defined herein
shall have the meanings set forth in the Security Agreement.

          5.   Counterparts. This Amendment may be executed in multiple
counterparts, each of which shall be deemed to be an original and all of which,
taken together, shall constitute one and the same agreement. Delivery of an
executed counterpart of this Amendment by facsimile transmission shall be as
effective as delivery of a manually executed counterpart hereof.

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          IN WITNESS WHEREOF, the Borrower has executed this Amendment as of the
date first above written.

                                    MAY & SPEH, INC.



                                    By: /s/ Eric M. Loughmiller
                                        -----------------------------------
                                    Title:  Executive Vice President, Chief
                                            Financial Officer and Secretary
                                            -------------------------------

ATTEST

By: /s/ Willard E. Engel Jr.
    --------------------------------------
Its: VP Treasurer/Chief Accounting Officer
     -------------------------------------



                                    THE NORTHERN TRUST COMPANY,
                                     as Agent


                                    By:                      
                                        --------------------------   
                                    Title:                  
                                           -----------------------


Accepted and Agreed to By:

THE NORTHERN TRUST COMPANY


By:
    ------------------------------
Title:
       ---------------------------


HARRIS TRUST AND SAVINGS BANK


By: /s/ John M. Dillon
    ------------------------------
Title:  Vice President 
       ---------------------------

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