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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

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                                   FORM 10-K/A
                                (AMENDMENT NO. 1)

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[X]  ANNUAL  REPORT  PURSUANT TO SECTION 13 OR 15(D) OF THE  SECURITIES
     EXCHANGE ACT OF 1934 FOR THE FISCAL YEAR ENDED DECEMBER 31, 1999
                                    OR
[ ]  TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES
     EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM           TO
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                        COMMISSION FILE NUMBER 000-29335

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                              WITNESS SYSTEMS, INC.
             (Exact name of registrant as specified in its charter)

                 DELAWARE                                       23-2518693
     (State or other jurisdiction of                         (I.R.S. Employer
      incorporation or organization)                         Identification No.)
           1105 SANCTUARY PARKWAY
                SUITE 210                                          30004
           ALPHARETTA, GEORGIA
    (Address of principal executive offices)                    (Zip code)

         Registrant's telephone number, including area code 770-754-1900

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        Securities registered pursuant to Section 12(b) of the Act: None

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

        TITLE OF EACH CLASS                 NAME OF EXCHANGE ON WHICH REGISTERED
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 Common Stock, par value $.01 per share       NASDAQ - National Market System



Purpose of Amendment: To include the information required by Part IV, Item 14(a)
of the Company's Form 10-K which was filed with the Securities and Exchange
Commission on March 24, 2000.
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                          INDEPENDENT AUDITORS' REPORT


The Board of Directors
Witness Systems, Inc.:

         We have audited the accompanying consolidated balance sheets of Witness
Systems, Inc. and subsidiary (the "Company") as of December 31, 1998 and 1999,
and the related consolidated statements of operations, stockholders' deficit and
cash flows for each of the years in the three-year period ended December 31,
1999. These consolidated financial statements are the responsibility of the
Company's management. Our responsibility is to express an opinion on these
consolidated financial statements based on our audits.

         We conducted our audits in accordance with generally accepted auditing
standards. Those standards require that we plan and perform the audit to obtain
reasonable assurance about whether the financial statements are free of material
misstatement. An audit includes examining, on a test basis, evidence supporting
the amounts and disclosures in the financial statements. An audit also includes
assessing the accounting principles used and significant estimates made by
management as well as evaluating the overall financial statement presentation.
We believe that our audits provide a reasonable basis for our opinion.

         In our opinion, the consolidated financial statements referred to above
present fairly, in all material respects, the financial position of Witness
Systems, Inc. and subsidiary at December 31, 1998 and 1999, and the results of
their operations and their cash flows for each of the years in the three-year
period ended December 31, 1999 in conformity with generally accepted accounting
principles.

                                                 /s/  KPMG LLP

Atlanta, Georgia
February 21, 2000


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                                   SIGNATURES

         Pursuant to the requirements of Section 13 of 15(d) of the Securities
Exchange Act of 1934, the registrant has duly caused this report to be signed on
its behalf by the undersigned, thereunto duly authorized, in the City of
Alpharetta, State of Georgia, on September 26, 2000.


Dated: September 26, 2000

                              WITNESS SYSTEMS, INC.


                              BY: /s/ David B. Gould
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                                      David B. Gould
                                      Chairman of the Board, President and
                                      Chief Executive Officer