EXHIBIT 99.1





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



         In connection with the Quarterly Report on Form 10-Q of Plexus Corp.
("Plexus") for the period ended June 30, 2002, as filed with the Securities and
Exchange Commission on the date hereof (the "Report"), I, Dean A Foate, Chief
Executive Officer of Plexus, certify, pursuant to 18 U.S.C. Section 1350, as
adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

         (1) The Report fully complies with the requirements of section 13(a) or
15(d) of the Securities Exchange Act of 1934; and

         (2) The information contained in the Report fairly presents, in all
material respects, the financial condition and results of operations of Plexus.

/s/ Dean A. Foate
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Dean A Foate
Chief Executive Officer, Plexus
August 14, 2002