FIRST AMENDMENT TO
                 AGREEMENT AND PLAN OF MERGER AND REORGANIZATION
                                       AND
                     EMPLOYMENTAND NON-COMPETITION AGREEMENT

         THIS FIRST AMENDMENT TO AGREEMENT AND PLAN OF MERGER AND REORGANIZATION
and  EMPLOYMENT  AND  NON-COMPETITION  AGREEMENT  (hereinafter  this  "Amendment
Agreement")  is  made  and  entered  into  effective  as of May  17,  1999  (the
"Effective  Date"), by and among Fair, Isaac and Company,  Incorporated  ("Fair,
Isaac"),  a Delaware  corporation;  Credit & Risk  Management  Associates,  Inc.
("CRMA"), a Delaware  corporation;  and Donald J. Sanders  ("Sanders"),  Paul A.
Makowski ("Makowski"), and Lawrence E. Dukes("Dukes") (collectively, the "former
CRMA Shareholders").


                                    RECITALS:

         A.   Fair,  Isaac,  as buyer,  entered into that certain  Agreement and
              Plan of Merger and  Reorganization  dated as of September 30, 1996
              (the "Merger  Agreement") to acquire by forward  subsidiary merger
              all of  the  assets  and  business  of  Credit  & Risk  Management
              Associates, Inc., as seller; and the former CRMA Shareholders,  as
              the owners of all of the issued and  outstanding  capital stock of
              CRMA (the "Merger"),  disposed of their interests in CRMA upon the
              terms and conditions set forth therein. CRMA is now a wholly-owned
              subsidiary of Fair, Isaac.

         B.   The Merger  Agreement  provided for Earnout Payments to the former
              CRMA  Shareholders  for each of the fiscal years ending  September
              30, 1997, September 30, 1998 and September 30, 1999.

         C.   The  parties  desire to amend the  terms of the  Merger  Agreement
              governing such Earnout  Payments to provide for termination of the
              Earnout Payments, on the terms and conditions set forth below.

         D.   In   connection   with  the  Merger,   each  of  the  former  CRMA
              Shareholders    entered   into   a   five-year    Employment   and
              Non-Competition  Agreement  with Fair,  Isaac as of September  30,
              1996 (the  "Employment  Agreement")  and now  desire to amend that
              Agreement as to Sanders and Dukes and terminate  that Agreement as
              to Makowski, as set forth herein.

         NOW, THEREFORE,  in consideration of the  representations,  warranties,
covenants and agreements contained herein, and for other valuable consideration,
the receipt and adequacy of which is hereby  acknowledged,  the parties mutually
agree as follows

1.   Meaning of Terms: Effective Date.

     Except as otherwise stated in this Amendment Agreement, (a) all capitalized
     terms in this Amendment Agreement will have the respective defined meanings
     as stated in the Merger Agreement, and (b) the terms and provisions of this
     Amendment  Agreement  will be  considered to be effective as of the date of
     this Amendment Agreement.

                                       1                             EXHIBIT 2.3




2.   Termination of Earnout Payments; Amendment of Employment Agreement.

     (a) For   and  in   consideration   of  the  sum  of   $2,108,402.00   (the
         "Consideration"),  the former CRMA Shareholders  agree as follows:  (i)
         Any and all obligations  relating to Earnout Payments including but not
         limited to those arising under  Sections 2.2, 2.8 and 5.9 of the Merger
         Agreement are  terminated as of the  Effective  Date;  and the parties'
         rights and obligations thereunder are hereby replaced and superseded by
         the terms of this Agreement.

         (ii) On the Effective Date, Sanders and Dukes shall execute and deliver
         an amendment to the  Employment  Agreement for each such  individual in
         the form attached hereto as Exhibit A.

         (iii) On the  Effective  Date,  Makowski  shall execute and deliver the
         termination of the Employment  Agreement in the form attached hereto as
         Exhibit B.

     (b) The Consideration shall be paid thirty-one percent (31%) in the form of
         Buyer  Common  Stock  valued at their  Average  Market  Price as of the
         Effective  Date in proportion to their  holdings of Seller Shares (such
         holdings  are defined in the Merger  Agreement to be 500 shares each of
         1500 shares total).  The Buyer Common Stock issued  hereunder  shall be
         subject to the Registration  Rights Agreement  described in Section 2.2
         of the Merger Agreement. The balance of the Consideration (69%) will be
         paid in cash and made by delivery of certified  or  cashier's  check or
         equivalent  instruments  or funds in  proportion  to their  holdings of
         Seller Shares  within ten (10) business days of receipt by Fair,  Isaac
         of the  Amendment  Agreement  and Exhibits  fully  executed by the CRMA
         Shareholders.

3.   General Release and Waiver of Claims.

     Except as expressly set forth in this Amendment Agreement, each former CRMA
     Shareholder releases,  remises and forever discharges CRMA and Fair, Isaac,
     and Fair, Isaac and CRMA release,  remise and forever  discharge the former
     CRMA  Shareholders,  from any and all claims,  counterclaims,  liabilities,
     demands  and causes of action of any  nature  whatsoever  whether  known or
     unknown,  fixed  or  contingent,  matured  or  unmatured,  arising  out of,
     connected  with or incidental  to, the Earnout  Payments  determined  under
     Section 2.2, and 2.8 (including but not limited to those under Section 5.9)
     of the Merger  Agreement up to and as of the Effective Date,  including but
     not limited to claims that may have existed or were  pending or  threatened
     before the Effective  Date of this  Agreement (all of which are referred to
     collectively as the "Claims").  The provisions,  waivers,  releases of this
     Section 3 shall  inure to the  benefit of the  parties,  including  without
     limitation, their agents, employees, attorneys, representatives,  officers,
     directors,  divisions,  participants,  subsidiaries,  Affiliates,  assigns,
     heirs,  successors in interests and  shareholders.  The  provisions  herein
     shall  survive  the full  performance  of all the  terms of this  Amendment
     Agreement and the Merger Agreement

     This is intended as a full settlement and compromise of each, every and all
     Claims.  The parties  acknowledge  that they may have claims  against  each
     other of which  they have no  knowledge  at the time of  execution  of this
     Amendment  Agreement.  The parties  agree that the waivers and  releases in
     this  Section  3, are  specifically  intended  to and do extend to  claims,
     demands,  or causes of action of which they have no knowledge.  The parties
     specifically  waive the  benefit of Section  1542 of the  California  Civil
     Code, which provides as follows:

       "A GENERAL  RELEASE DOES NOT EXTEND TO CLAIMS WHICH THE CREDITOR DOES NOT
       KNOW OR SUSPECT TO EXIST IN HIS FAVOR AT THE TIME OF

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       EXECUTING THE RELEASE WHICH IF KNOWN BY HIM MUST HAVE MATERIALLY AFFECTED
       HIS SETTLEMENT WITH THE DEBTOR."

4. Incorporation by Reference.

The  Recitals  and  Exhibits  A and B to this  Amendment  Agreement  are  hereby
incorporated by reference.

5. Construction.

Except as explicitly  modified by this  Amendment  Agreement no other changes to
the Merger  Agreement are being made and all provisions of the Merger  Agreement
shall  remain in full force and effect.  This  Agreement  does not  constitute a
renewal or novation of the Merger Agreement.

The  headings  and  captions  of  this  Amendment  Agreement  are  provided  for
convenience   only  and  are  intended  to  have  no  effect  on  construing  or
interpreting  this  Amendment  Agreement.  The  language  in all  parts  of this
Amendment  Agreement  shall  be in all  cases  construed  according  to its fair
meaning and not strictly for out against any party.

6. Counterparts.

This Amendment Agreement may be executed in multiple counterparts, each of which
shall be deemed an original,  but all of which taken together  shall  constitute
one and the same instrument.  Execution and delivery of this Amendment Agreement
be exchange of facsimile  copies bearing  facsimile  signature of a party hereto
shall  constitute a valid and binding  execution and delivery of this  Amendment
Agreement  by such  party.  Such  facsimile  copy shall  constitute  enforceable
original documents.

         In Witness  Whereof,  this Amendment  Agreement has been executed as of
the date first set forth above.


                                       FAIR, ISAAC AND COMPANY, INCORPORATED

                                       By ______________________________________
                                         Its ___________________________________



                                       CREDIT & RISK MANAGEMENT ASSOCIATES, INC.

                                       By ______________________________________
                                         Its ___________________________________



                                       _________________________________________
                                       Donald J. Sanders



                                       _________________________________________
                                       Paul A. Makowski

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                                       _________________________________________
                                       Lawrence E. Dukes


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