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                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   FORM 10-K/A

                               AMENDMENT NO. 1 TO
              ANNUAL REPORT PURSUANT TO SECTIONS 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

                   For the Fiscal Year Ended December 31, 2001

                         Commission File Number 0-22667

                             MERCATOR SOFTWARE, INC.
             (Exact name of registrant as specified in its charter)

               Delaware                               06-1132156
      (State or other jurisdiction                 (I.R.S. Employer
    of incorporation or organization)             Identification No.)

      45 Danbury Road, Wilton, CT                       06897
(Address of principal executive offices)              (Zip Code)

               Registrant's telephone number, including area code:
                                  203-761-8600

        Securities Registered Pursuant to Section 12(b) of the Act: NONE

Securities Registered Pursuant to Section 12(g) of the Act:
Common Stock, par value $.01 per share

Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                 Yes [X] No [_]

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K.

                                 Yes [_] No [_]

The aggregate market value of the voting and non-voting common equity held by
non-affiliates of the registrant as of March 8, 2002 was approximately
$184,662,245 based upon $5.46 per share, the last reported sale price of the
Common Stock on the Nasdaq National Market on that date. As of March 8, 2002
there were 33,820,924 shares of the Registrant's Common Stock outstanding.

                       DOCUMENTS INCORPORATED BY REFERENCE

                                      None.

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Explanatory Note: This Form 10K/A is being filed in order to include attachments
to Exhibits 10.34 and 10.35 to the Registrant's Annual Report on Form 10-K for
the year ended December 31, 2001, previously filed with the Commission.

                                     Part IV

Item 14. Exhibits, Financial Statement Schedules, and Reports on Form 8-K

3.(a)    The Exhibits listed in the Exhibit Index immediately preceding the
         Exhibits are filed as a part of this Annual Report on Form 10-K/A.


                                   SIGNATURES

     Pursuant to the requirements of Section 13 or 15(d) of the Securities Act,
the registrant has duly caused this report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                                     By: /s/ Roy C. King
                                        --------------------------------------
                                         Roy C. King
                                         Chairman of the Board of Directors,
                                         Chief Executive Officer and President

Date:  March 22, 2002


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                                  EXHIBIT INDEX

Exhibit No.
Regulation S-K
Item 601
Designation                         Exhibit Description
-----------                         -------------------
2.1            Agreement and Plan of Reorganization dated as of September 30,
               1999 by and among Mercator Software, Inc. Natchez Acquisition
               Corp. and Novera Software, Inc. /(1)/

2.2            Stock Purchase Agreement dated as of March 18, 1999 by and among
               Mercator Software and each of the stockholders of Braid Group
               Limited/(8)/

2.3            Asset Transfer Agreement dated as of November 13, 1998 by and
               among the Mercator Software, Software Consulting Partners and the
               sole stockholder of Software Consulting Partners/(7)/

3(i)-1         Amended and Restated Certificate of Incorporation/(5)/

    -2         Certificate of Designations specifying the terms of the Series A
               Junior Participating Preferred Stock of Mercator Software/(4)/

3(ii)          Registrant's Amended and Restated Bylaws/(3)/

4.1            Form of Specimen Certificate for Registrant's Common Stock/(2)/

4.2            Stockholders Agreement dated as of June 1, 1989, as amended/(2)/

4.3            1989 Stock Purchase Agreement dated as of June 1, 1989, as
               amended/(2)/

4.4            Series E Preferred Stock Purchase Agreement dated as of May 15,
               1997 between Mercator Software and the Purchasers named
               therein/(2)/

4.5            Rights Agreement between the Registrant and The Bank of New York
               dated as of September 2, 1998/(3)/

4.6            Securities Purchase Agreement dated as of December 11, 2001 among
               Registrant and certain Purchasers/(10)/

4.7            Form of Warrant issued to Purchasers dated December 11,
               2001/(10)/

4.8            Registration Rights Agreement between the Registrant and Silicon
               Valley Bank dated June 22, 2001/(9)/

4.9            Warrant to Purchase Stock issued to Silicon Valley Bank on June
               22, 2001/(9)/

4.10           Warrant Agreement dated as of December 11, 2001 between William
               Blair & Company, L.L.C. and the Registrant/(11)/

4.11           Warrant Agreement dated as of January 7, 2002 between MAST Global
               Limited and the Registrant/(11)/


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4.12           Warrant Agreement dated as of June 20, 2001 between Morgan Howard
               Group International Limited and the Registrant/(11)/

10.1           *Employment Agreement dated as of January 1, 1999 between
               Registrant and Albert Denz/(12)/

10.2           *Employment Agreement dated as of January 16, 2001 between
               Registrant and Roy C. King/(12)/

10.3           *Registrant's 1993 Stock Option Plan and related documents/(2)/

10.4           *Registrant's 1997 Equity Incentive Plan, as amended/(13)/

10.5           *Registrant's 1997 Directors Stock Option Plan/(2)/

10.6           *Registrant's 1997 Employee Stock Purchase Plan/(2)/

10.7           *Registrant's Profit Participation Plan/(2)/

10.8           *Form of Indemnification Agreement entered into by Registrant
               with each of its directors and executive officers/(2)/

10.9           Lease Agreement dated as of January 2, 1990 between Registrant
               and Robert D. Scinto, as amended/(2)/

10.10          Lease Agreement dated as of June 26, 2000 between Registrant and
               Bannockburn Development Company/(12)/

10.11          Lease Agreement dated as of January 29, 2001 between Registrant
               and CDR Federal LLC/(12)/

10.12          *Letter Agreement dated as of September 20, 2000, between
               Registrant and Constance Galley/(5)/

10.13          *Letter Agreement dated as of December 5, 1995 between Registrant
               and Eric Amster/(2)/

10.14          *Separation and Release Agreement dated as of March 13, 2001
               between Registrant and Saydean Zeldin/(13)/

10.15          Accounts Receivable Financing Agreement between the Registrant
               and Silicon Valley Bank dated June 22, 2001/(9)/

10.16          Credit Agreement between Registrant and Fleet Nation Bank dated
               as of February 25, 2000/(6)/

10.17          Lease Agreement between Registrant and Wilton Realty Investors
               Corp. dated June 6, 2000/(5)/

10.18          *Agreement between Registrant and James P. Schadt dated as of
               August 21, 2000/(5)/

10.19          *Letter Agreement between Registrant and James P. Schadt dated as
               of November 21, 2000/(12)/

10.20          *Letter Agreement between Registrant and Richard Applegate dated
               as of July 12, 2001/(13)/


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10.21          *Agreement between Registrant and Patricia Boggs dated December
               22, 2000/(12)/

10.22          Lease dated April 20, 2001 between the Registrant and the
               Prudential Assurance Company Limited/(9)/

10.23          *Agreement between the Registrant and David Linthicum, dated as
               of March 12, 2001/(13)/

10.24          *Agreement between the Registrant and Eileen Garry dated as of
               May 25, 2001/(13)/

10.25          *Agreement between the Registrant and Ron Smith dated as of May
               31, 2001/(13)/

10.26          *Agreement between the Registrant and Robert J. Farrell dated as
               of June 13, 2001/(13)/

10.27          *Agreement between the Registrant and Kenneth J. Hall dated as of
               June 28, 2001/(13)/

10.28          *Agreement between the Registrant and Gregory G. O'Brien dated as
               of July 11, 2001/(13)/

10.29          *Agreement between the Registrant and Michael Wheeler dated as of
               August 16, 2001/(13)/

10.30          *Agreement between the Registrant and Jill Donohoe dated as of
               September 18, 2001/(13)/

10.31          *Agreement between the Registrant and Mark Register dated as of
               September 25, 2001/(13)/

10.32          *Change of Control Benefits Plan dated as of December 18, 2001

10.33          Accounts Receivable Financing Modification Agreement Dated as of
               September 18, 2001 between the Registrant and Silicon Valley Bank

10.34          +Second Loan Modification Agreement dated as of November 28,
               2001 between the Registrant and Silicon Valley Bank

10.35          +Deed of Office Lease dated February 22, 2002 between 11720
               Sunrise Corp., L.L.C. and the Registrant

13             Consolidated Financial Statements as of and for the years ended
               December 31, 2001 and 2000

21             Subsidiaries of the Company

23             Consent of Independent Auditors

--------------------------------

(1)  Previously filed as an exhibit to our current Report on Form 8-K dated
     September 30, 1999 and incorporated herein by reference.

(2)  Previously filed as an exhibit to our Registration Statement on Form S-1
     (File No. 333-27293) dated June 5, 1998 and incorporated herein by
     reference.

(3)  Previously filed as an exhibit to our Registration Statement on Form 8-A
     (File No. 000-22667) filed on September 4, 1998 and incorporated herein by
     reference.

(4)  Previously filed as an exhibit to our Current Report on Form 8-K filed on
     September 4, 1998 and incorporated herein by reference.


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(5)  Previously filed as an exhibit to our Quarterly Report on Form 10-Q for the
     quarter ended September 30, 2000 and incorporated herein by reference.

(6)  Previously filed as an exhibit to our Quarterly Report on Form 10-Q for the
     quarter ended June 30, 2000 and incorporated herein by reference.

(7)  Previously filed as an exhibit to our Current Report on Form 8-K dated
     November 13, 1998 and incorporated herein by reference.

(8)  Previously filed as an exhibit to our Current Report on Form 8-K dated
     March 18, 1999 and incorporated herein by reference.

(9)  Previously filed as an exhibit to our Quarterly Report on Form 10-Q for the
     quarter ended June 30, 2001 and incorporated herein by reference.

(10) Previously filed as an exhibit to our Current Report on Form 8-K dated
     December 21, 2001 and incorporated herein by reference.

(11) Previously filed as an exhibit to our Registration Statement on Form S-3
     (File No. 333-76882) dated January 17, 2002 and incorporated herein by
     reference.

(12) Previously filed as an exhibit to our Annual Report on Form 10-K for the
     fiscal year ended December 31, 2000 and incorporated herein by reference.

(13) Previously filed as an exhibit to our Quarterly Report on Form 10-Q for the
     quarter ended September 30, 2001 and incorporated herein by reference.

*    Indicates a management contract or compensatory plan, contract or
     arrangement.

+    Filed herewith as amended.

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