Exhibit 99.1

      CERTIFICATION OF CHIEF EXECUTIVE OFFICER AND CHIEF FINANCIAL OFFICER
                                   PURSUANT TO
                             18 U.S.C. SECTION 1350,
                             AS ADOPTED PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

I, Andrew Zimmerman, certify, pursuant to 18 U.S.C. Section 1350, as adopted
pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that the Quarterly
Report of Predictive Systems, Inc. on Form 10-Q for the quarterly period ended
June 30, 2002 fully complies with the requirements of Section 13(a) or 15(d) of
the Securities Exchange Act of 1934 and that information contained in such
Quarterly Report fairly presents in all material respects the financial
condition and results of operations of Predictive Systems, Inc.

By:      /s/  Andrew Zimmerman
Name:    Andrew Zimmerman
Title:   Chief Executive Officer

I, Neeraj Sethi, certify, pursuant to 18 U.S.C. Section 1350, as adopted
pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that the Quarterly
Report of Predictive Systems, Inc. on Form 10-Qfor the quarterly period ended
June 30, 2002 fully complies with the requirements of Section 13(a) or 15(d) of
the Securities Exchange Act of 1934 and that information contained in such
Quarterly Report fairly presents in all material respects the financial
condition and results of operations of Predictive Systems, Inc.

By:      /s/  Neeraj Sethi
Name:    Neeraj Sethi
Title:   Chief Financial Officer