<DOCUMENT>
<TYPE>10-K/A
<SEQUENCE>1
<FILENAME>d10ka.txt
<DESCRIPTION>FORM 10-K/A
<TEXT>
<PAGE>

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   FORM 10-K/A

AMENDMENT No. 1 TO ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
SECURITIES EXCHANGE ACT of 1934

For the fiscal year ended December 31, 2001


                           Commission File No. 1-11859


                                PEGASYSTEMS INC.
             ------------------------------------------------------
             (Exact name of Registrant as specified in its charter)

                                  Massachusetts
         --------------------------------------------------------------
         (State or other jurisdiction of incorporation or organization)

                  (IRS Employer Identification No. 04-2787865)
                                                   ----------

         101 Main Street
          Cambridge, MA                                    02142-1590
----------------------------------------                   ----------
(Address of principal executive offices)                   (zip code)

                                 (617) 374-9600
              ----------------------------------------------------
              (Registrant's telephone number, including area code)

           Securities registered pursuant to Section 12(b) of the Act:

                                      None

           Securities registered pursuant to Section 12(g) of the Act:

                     Common Stock, $.01 par value 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 the 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. |X|

     As of March 14, 2002, the aggregate market value of the Registrant's voting
stock held by non-affiliates of the Registrant was approximately $59 million.

     There were 33,413,522 shares of the Registrant's common stock, $.01 par
value per share, outstanding on March 14, 2002.

<PAGE>

The undersigned Registrant hereby amends the following Item 13 of its 2001
Annual Report on Form 10-K filed with the Securities and Exchange Commission on
March 28, 2002, to read in its entirety as follows:

Item 13   CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

     On May 10, 2001, we entered into an employment agreement with Joseph J.
Friscia setting forth his responsibilities and compensation. The agreement
requires us to pay Mr. Friscia an annual base salary of $250,000 and all legal
defense expenses arising out of Mr. Friscia's employment. In addition, subject
to Mr. Friscia executing a general release of claims against us, in the event we
terminate Mr. Friscia's employment without cause or Mr. Friscia terminates his
employment for any reason, the agreement provides for one year of base salary
continuation, one year of continued coverage under our group health insurance
plan and up to $10,000 of outplacement support services. Under the agreement,
Mr. Friscia confirmed his earlier agreement not to compete with our business
during the term of his employment and for eighteen months thereafter and also
agreed not to solicit any of our employees for a period of eighteen months after
the termination of his employment.

     During 2001 there were no other transactions involving more than $60,000,
other than executive compensation and benefits earned in the normal course of
business, nor are any proposed, between the Company and any executive officer,
Director, 5% beneficial owner of our Common Stock or equivalents, or any
immediate family member of any of the foregoing, in which any such persons or
entities had or will have a direct or indirect material interest.

     We have adopted a policy which provides that transactions between the
Company and its officers, Directors, principal stockholders and their affiliates
must be on terms no less favorable to the Company than could be obtained from
unrelated third parties and must be approved by a majority of the disinterested
members of the Company's Board of Directors.


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<PAGE>

                                   SIGNATURES

     Pursuant to the requirements to Section 13 or 15(d) of the Securities
Exchange Act of 1934, the Registrant has duly caused this amendment on Form
10-K/A to be signed on its behalf by the undersigned, thereunto duly authorized.

                                     PEGASYSTEMS INC.

                                     By: /s/ CHRISTOPHER SULLIVAN
                                        --------------------------
                                        Christopher Sullivan
                                        Senior Vice President, Chief Financial
                                        Officer, and Treasurer

Date:   April 19, 2002


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