UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINTGON, D.C. 20549

                                  FORM 11 -- K

     [X]         ANNUAL REPORT PURSUANT TO SECTION 13 OR 15 (d) OF THE
                 SECURITIES EXCHANGE ACT OF 1934 [FEE REQUIRED]

For the fiscal year ended....................December 31, 2002..................

                                       OR

     [ ]         TRANSITION REPORT PURSUANT TO SECTION 15 (d) OF THE SECURITIES
                 EXCHANGE ACT OF 1934 [NO FEE REQUIRED]

For the transition period from..............................to..................

      Commission file number...........000-14824............[Plexus Corp.]

A.  Full title of the plan and the address of the plan, if different from that
    of the issuer named below:

                        PLEXUS CORP. 401(k) SAVINGS PLAN

B.  Name of issuer of the securities held pursuant to the plan and the address
    of its principal executive office:


                                  PLEXUS CORP.
                             55 JEWELERS PARK DRIVE
                                NEENAH, WI 54956





PLEXUS CORP.
401(K) SAVINGS PLAN
INDEX TO FINANCIAL STATEMENTS
-------------------------------------------------------------------------------

                                                                       PAGE(s)

REPORT OF INDEPENDENT ACCOUNTANTS                                        1

FINANCIAL STATEMENTS

Statements of Net Assets Available for Benefits
 as of December 31, 2002 and 2001                                        2

Statement of Changes in Net Assets Available for Benefits
 for the year ended December 31, 2002                                    3

Notes to Financial Statements                                           4-7

SUPPLEMENTAL SCHEDULES

Schedule I: Schedule of Assets (Held at End of Year)
  as of December 31, 2002                                                8








Note:  Other schedules required by Section 2520.103-10 of the Department of
       Labor's Rules and Regulations for Reporting and Disclosure under the
       Employee Retirement Income Security Act of 1974 have been omitted
       because they are not applicable.













                        REPORT OF INDEPENDENT ACCOUNTANTS


To the Participants and Administrator
of the Plexus Corp. 401(k) Savings Plan


In our opinion, the accompanying statements of net assets available for benefits
and the related statement of changes in net assets available for benefits
present fairly, in all material respects, the net assets available for benefits
of the Plexus Corp. 401(k) Savings Plan (the "Plan") as of December 31, 2002 and
2001, and the changes in net assets available for benefits for the year ended
December 31, 2002, in conformity with accounting principles generally accepted
in the United States of America. These financial statements are the
responsibility of the Plan's management; our responsibility is to express an
opinion on these financial statements based on our audits. We conducted our
audits of these statements in accordance with auditing standards generally
accepted in the United States of America, which 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,
assessing the accounting principles used and significant estimates made by
management, and evaluating the overall financial statement presentation. We
believe that our audits provide a reasonable basis for our opinion.

Our audits were conducted for the purpose of forming an opinion on the basic
financial statements taken as a whole. The supplemental Schedule of Assets (Held
at End of Year) is presented for the purpose of additional analysis and is not a
required part of the basic financial statements but is supplementary information
required by the Department of Labor's Rules and Regulations for Reporting and
Disclosure under the Employee Retirement Income Security Act of 1974. This
supplemental schedule is the responsibility of the Plan's management. The
supplemental schedule has been subjected to the auditing procedures applied in
the audits of the basic financial statements and, in our opinion, is fairly
stated in all material respects in relation to the basic financial statements
taken as a whole.





/s/ PricewaterhouseCoopers LLP
June 16, 2003

                                        1




PLEXUS CORP. 401(K) SAVINGS PLAN
STATEMENTS OF NET ASSETS AVAILABLE FOR BENEFITS
DECEMBER 31, 2002 AND 2001
--------------------------------------------------------------------------------


                                                      2002              2001




                                                           
Assets
Investments (See Note 3)                        $  54,622,457      $ 84,660,171
Participant loans                                   2,493,835         3,010,849

Receivables:
  Employer's contribution                              76,547            93,180
  Participants' contributions                         217,433           278,203
                                                -------------      -------------
     Total receivables                                293,980           371,383
                                                -------------      -------------
Net assets available for benefits               $  57,410,272      $ 88,042,403
                                                =============      =============



   The accompanying notes are an integral part of these financial statements.



                                        2



PLEXUS CORP. 401(K) SAVINGS PLAN
STATEMENT OF CHANGES IN NET ASSETS AVAILABLE FOR BENEFITS
FOR THE YEAR ENDED DECEMBER 31, 2002
-------------------------------------------------------------------------------




                                                           
Additions
Additions to net assets attributed to:
 Investment (loss) income:
   Net depreciation in fair value of investments                 $(33,855,616)
   Interest and dividends                                           1,057,797
                                                                 ------------
                                                                  (32,797,819)
                                                                 ------------
   Contributions:
     Participants'                                                  7,467,156
     Employer's                                                     2,247,249
                                                                 ------------
                                                                    9,714,405
                                                                 ------------
     Total additions (net deductions)                             (23,083,414)

Deductions
Deductions from net assets attributed to:
  Benefits paid to participants                                     8,111,858
  Administrative expenses                                              32,449
                                                                 ------------
   Total deductions                                                 8,144,307
                                                                 ------------
  Net decrease before plan transfers                              (31,227,721)
Transfer from other plan                                              595,590
                                                                 ------------
  Net decrease                                                    (30,632,131)
Net assets available for benefits:
  Beginning of year                                                88,042,403
                                                                 ------------
  End of year                                                    $ 57,410,272
                                                                 ------------





   The accompanying notes are an integral part of these financial statements.




                                        3


PLEXUS CORP. 401(K) SAVINGS PLAN
NOTES TO FINANCIAL STATEMENTS
DECEMBER 31, 2002 AND 2001
--------------------------------------------------------------------------------

1.       DESCRIPTION OF PLAN

         The following description of the Plexus Corp. 401(k) Savings Plan (the
         "Plan") provides only general information. Participants should refer to
         the plan agreement for a more complete description of the Plan's
         provisions.

         GENERAL
         The Plan, originally effective January 1, 1989 and amended and restated
         effective March 1, 2000, is a contributory defined contribution plan
         covering substantially all employees of Plexus Corp. (the "Company")
         and affiliated employers, as defined, who have completed 90 days of
         service. The Plan is subject to the provisions of the Employee
         Retirement Income Security Act of 1974 ("ERISA").

         On January 1, 2002, the Qtron, Inc. 401(k) Profit Sharing Plan merged
         into the Plan. In connection with the merger, net assets totalling
         $595,590, representing the account balances of former participants of
         the Qtron, Inc. 401(k) Profit Sharing Plan, were transferred to the
         Plan in January 2002. The Plan was amended on January 1, 2002 to comply
         with the Economic Growth and Tax Relief Reconciliation Act of 2001 and
         certain other requirements under the Internal Revenue Code.

         CONTRIBUTIONS
         Employee pre-tax contributions are based on voluntary elections via
         phone or internet by the participants, directing the Company to defer a
         stated amount from the participant's compensation. Participants may
         elect to defer up to 18% of their annual compensation. The Company will
         make a matching contribution on behalf of a participant equal to 100%
         of the first 2.5% of the participant's compensation contributed to the
         Plan for participants who have completed one year of service.
         Contributions are limited by Section 401(k) of the Internal Revenue
         Code.

         INVESTMENT ALTERNATIVES
         Plan participants may direct their entire account balances in 1%
         increments to any of the various investment options offered by the
         Plan. Participants may change their investment options on a daily
         basis.

         PARTICIPANT ACCOUNTS AND ALLOCATIONS
         Participant recordkeeping is performed by MFS Retirement Services, Inc.
         ("MFS"). For all investment programs which are mutual funds, MFS
         maintains participant balances on a share method. Participant
         investments in the Plexus Unitized Stock Fund, Conservative Portfolio
         Option, Moderate Portfolio Option, Aggressive Portfolio Option, and MFS
         Fixed Fund are accounted for on a unit value method. Units and unit
         values for these funds as of December 31, 2002 and 2001 were as
         follows:




                                               UNITS                          UNIT VALUE

                                             DECEMBER 31,                    DECEMBER 31,
                                      -----------------------          -----------------------
                                          2002        2001                2002           2001
                                      ----------    ---------          ---------       --------

                                                                           
Plexus Unitized Stock Fund            3,304,143     3,391,372          $  3.43         $  9.80
Conservative Portfolio Option           124,056        76,942             9.45            9.89
Moderate Portfolio Option               157,975        98,710             7.25            8.72
Aggressive Portfolio Option             321,052       212,744             4.93            7.24
MFS Fixed Fund                        6,965,352     8,609,236             1.00            1.00


                                       4



PLEXUS CORP. 401(K) SAVINGS PLAN
NOTES TO FINANCIAL STATEMENTS
DECEMBER 31, 2002 AND 2001
--------------------------------------------------------------------------------

         Each participant's account is credited with the participant's
         contributions and allocations of Company contributions and plan
         earnings (losses). Allocations of plan earnings (losses) are based on
         participant account balances in relation to total fund account
         balances, as defined by the plan document.

         VESTING AND DISTRIBUTIONS
         Participants immediately vest in all contributions made to the Plan.
         Participant accounts are distributable in the form of a lump sum
         payment or substantially equal installments of cash or in whole shares
         of Company securities as elected by the participant upon retirement,
         termination of employment, death, disability, financial hardship or
         attainment of age 59-1/2. Participant account balances less than $5,000
         may be automatically distributed in a lump sum. In addition,
         participant accounts can be rolled over into an individual retirement
         account ("IRA") or another qualified defined contribution plan.
         Participant distributions may not be deferred past April 1 of the
         calendar year following the year in which the participant attains age
         70-1/2. Forfeitures of unclaimed distributions are used to reduce
         Company matching contributions.

         PARTICIPANT LOANS
         Participants may borrow from their accounts a minimum of $1,000 up to a
         maximum amount equal to the lesser of $50,000 or 50 percent of their
         vested account balance. Loan terms range up to five years. Loans are
         secured by the balance in the participant's account and bear interest
         at the prime rate plus one percent. Principal and interest is paid
         ratably through regular payroll deductions.


  2.     SUMMARY OF ACCOUNTING POLICIES

         ACCOUNTING METHOD
         The financial statements of the Plan are prepared under the accrual
         method of accounting.

         USE OF ESTIMATES
         The preparation of financial statements in conformity with accounting
         principles generally accepted in the United States of America requires
         management to make estimates and assumptions that affect the reported
         amounts of assets, liabilities, and changes therein, and disclosure of
         contingent assets and liabilities. Actual results could differ from
         those estimates.

         INVESTMENT VALUATION AND INCOME RECOGNITION
         The Plan's investments are stated at fair value. The share value of
         mutual funds is based on quoted market prices on the last business day
         of the plan year. The unit value of unitized funds and common trust
         funds is computed daily based on share price, dividend information and
         the value of the fund's short-term investments. Participant loans are
         stated at cost, which approximates fair value. The Plan presents in the
         statement of changes in net assets available for benefits, the net
         appreciation (depreciation) in the fair value of its investments which
         consists of the realized gains or losses and the unrealized
         appreciation (depreciation) on those investments. Purchases and sales
         of investments are recorded on a trade-date basis. Dividends are
         recorded on the ex-dividend date. Interest is recognized when earned.

                                       5



PLEXUS CORP. 401(K) SAVINGS PLAN
NOTES TO FINANCIAL STATEMENTS
DECEMBER 31, 2002 AND 2001
--------------------------------------------------------------------------------

         RISKS AND UNCERTAINTIES
         The Plan's investments are exposed to various risks, such as interest
         rate, market and credit risks. Due to the level of risk associated with
         certain investments and the level of uncertainty related to changes in
         the values of investments, it is at least reasonably possible that
         changes in risks in the near term would materially affect participants'
         account balances and the amounts reported in the statements of net
         assets available for benefits and the statement of changes in net
         assets available for benefits.

         PAYMENT OF BENEFITS
         Benefits are recorded when paid.

         ADMINISTRATIVE EXPENSES
         Certain expenses incurred in the administration of the Plan are paid by
         the Company and are not reflected within these financial statements.


3.       INVESTMENTS

         The following presents investments that represent 5 percent or more of
         the Plan's net assets:





                                                               2002              2001

                                                                    
       Plexus Corp. Common Stock, 1,230,759 and
        1,209,726 shares, respectively                    $ 10,806,064      $ 32,130,322

       MFS Capital Opportunities Fund, 712,203 and
        636,835 shares, respectively                         6,651,973         8,552,700

       Munder Index 500 Fund, 322,337 and 287,979
        shares, respectively                                 5,911,667         6,897,086

       MFS Value Fund, 333,231 and 294,242
        shares, respectively                                 5,504,974         5,714,175

       MFS Mid Cap Growth Fund, 703,317 and
        600,709 shares, respectively                         3,980,772         6,583,769

       MFS New Discovery Fund, 359,887 and
        273,935 shares, respectively                         4,113,507         4,708,936

       MFS Fixed Fund, 6,965,352 and
        8,609,236 units, respectively                        6,965,352         8,609,236

       American Europacific Growth Fund, 177,495
        and 162,628 shares, respectively                     4,077,054         4,369,813



                                       6



PLEXUS CORP. 401(K) SAVINGS PLAN
NOTES TO FINANCIAL STATEMENTS
DECEMBER 31, 2002 AND 2001
--------------------------------------------------------------------------------

         During 2002, the Plan's investments (including gains and losses on
         investments bought and sold, as well as held during the year)
         depreciated in value by $(33,855,616), as follows:


                                               
                     Mutual funds                  $ (12,751,752)
                     Common stock                    (21,103,864)
                                                   --------------
                                                   $ (33,855,616)
                                                   --------------




4.       AMOUNTS ALLOCATED TO WITHDRAWN PARTICIPANTS

         Approximately $7,492,151 and $6,640,836 of plan assets have been
         allocated to the accounts of persons who are no longer active
         participants of the Plan as of December 31, 2002 and 2001,
         respectively, but who have not yet received distributions as of that
         date.


5.       TAX STATUS

         The Internal Revenue Service has determined and informed the Company by
         a letter dated May 6, 1998, that the Plan is designed in accordance
         with applicable sections of the Internal Revenue Code ("IRC"). The Plan
         has been amended since receiving the determination letter, and the
         Company is in the process of requesting a new letter. However, the plan
         administrator believes that the Plan is designed and is currently being
         operated in compliance with the applicable requirements of the IRC.


6.       PLAN TERMINATION

         Although it has not expressed any intent to do so, the Company has the
         right under the Plan to discontinue its contributions at any time and
         to terminate the Plan subject to the provisions of ERISA.


7.       RELATED PARTY TRANSACTIONS

         Certain plan investments represent shares of funds managed by MFS
         Heritage Trust Company, the trustee of the Plan, employer securities
         and participant loans. Transactions involving these investments are
         considered party-in-interest transactions. These transactions are not,
         however, considered prohibited transactions under 29 CFR 408(b) of the
         ERISA regulations.


8.       SUBSEQUENT EVENT

         Effective January 1, 2003, the MCMS Retirement Plan was merged into the
         Plan. In connection with the merger, net assets approximating
         $7,000,000, representing the account balances of former participants of
         the MCMS Retirement Plan, were transferred to the Plan on that date.

                                       7



PLEXUS CORP. 401(K) SAVINGS PLAN
FORM 5500, SCHEDULE OF ASSETS (HELD AT END OF YEAR)
DECEMBER 31, 2002
--------------------------------------------------------------------------------




          IDENTITY OF ISSUER,
             BORROWER, LESSOR                                                                         CURRENT
             OR SIMILAR PARTY                            DESCRIPTION OF INVESTMENT                     VALUE

                                                                                          
*   Plexus Corp. Common Stock                          Common Stock                              $      10,806,064

*   MFS Money Market Fund                              Mutual Fund                                         537,947

*   MFS Capital Opportunities Fund                     Mutual Fund                                       6,651,973

*   MFS Mid Cap Growth Fund                            Mutual Fund                                       3,980,772

*   MFS Value Fund                                     Mutual Fund                                       5,504,974

*   MFS New Discovery Fund                             Mutual Fund                                       4,113,507

*   MFS Fixed Fund                                     Common Trust Fund                                 6,965,352

    American EuroPacific Growth Fund                   Mutual Fund                                       4,077,054

    Janus Aspen Worldwide Fund                         Mutual Fund                                       1,706,534

    Munder Index 500 Fund                              Mutual Fund                                       5,911,667

    Dreyfus Premier Technology Fund                    Mutual Fund                                         769,326

    American Balanced Fund                             Mutual Fund                                       1,426,798

    Calvert Income Fund                                Mutual Fund                                       2,170,489
                                                                                                 -----------------
                                                                                                 $      54,622,457
                                                                                                 -----------------
*   Participant Loans                                  Interest rates ranging from 5.25%
                                                       to 10.50%; maturity dates ranging
                                                       from 2003 to 2011                         $       2,493,835
                                                                                                 -----------------


*  Party-in-interest.

See Report of Independent Accountants.



                                       8









                                   SIGNATURES

The Plan. Pursuant to the requirements of the Securities Exchange Act of 1934,
the trustees (or other persons who administer the employee benefit plan) have
duly caused this annual report to be signed on its behalf by the undersigned
hereunto duly authorized.

PLEXUS CORP. 401(k) SAVINGS PLAN

Date:  June 27, 2003

                               /s/ Jos. D. Kaufman
                              -------------------------------------------------
                               Joseph D. Kaufman
                               Plexus Corp 401(k) Savings Plan Fiduciary
                               Committee Member


                                       9