Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
KRONSER J ROBERT
  2. Issuer Name and Ticker or Trading Symbol
PLEXUS CORP [PLXS]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Executive VP and CT&SO
(Last)
(First)
(Middle)
55 JEWELERS PARK DRIVE
3. Date of Earliest Transaction (Month/Day/Year)
02/24/2006
(Street)

NEENAH, WI 54956
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock, $.01 par value 02/24/2006   M   15,000 A $ 12.94 35,002 D  
Common Stock, $.01 par value 02/24/2006   S   15,000 D $ 33.7764 20,002 D (1)  
Common Stock, $.01 par value 02/24/2006   M   6,797 A $ 14.015 26,799 D  
Common Stock, $.01 par value 02/24/2006   S   6,797 D $ 34.0148 20,002 D (1)  
Common Stock, $.01 par value 02/24/2006   M   2,450 A $ 14.015 22,452 D  
Common Stock, $.01 par value 02/24/2006   S   2,450 D $ 34 20,002 D (1)  
Common Stock, $.01 par value 02/24/2006   M   5,000 A $ 15.825 25,002 D  
Common Stock, $.01 par value 02/24/2006   S   5,000 D $ 34.0148 20,002 D (1)  
Common Stock, $.01 par value 02/24/2006   M   103 A $ 15.825 20,105 D  
Common Stock, $.01 par value 02/24/2006   S   103 D $ 34.0148 20,002 D (1)  
Common Stock, $.01 par value 02/24/2006   M   9,897 A $ 15.825 29,899 D  
Common Stock, $.01 par value 02/24/2006   S   9,897 D $ 33.7764 20,002 D (1)  
Common Stock, $.01 par value               6,049 D (2)  

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Option to buy (1) $ 6.1563             03/18/1997 03/18/2007 Common Stock 20,000   20,000 D  
Option to buy (1) $ 10.594             04/23/1998 04/23/2008 Common Stock 10,130   10,130 D  
Option to buy (1) $ 15.125             04/21/1999 04/21/2009 Common Stock 9,108   9,108 D  
Option to buy (1) $ 35.5469             04/24/2000 04/24/2010 Common Stock 18,000   18,000 D  
Option to buy (1) $ 23.55             04/06/2001 04/06/2011 Common Stock 19,000   19,000 D  
Option to buy (1) $ 25.285             04/22/2002 04/22/2012 Common Stock 9,000   9,000 D  
Option to buy (1) $ 8.975             01/30/2003 01/30/2013 Common Stock 7,190   7,190 D  
Option to buy (1) $ 14.015 02/24/2006   M     9,247 05/11/2005 08/14/2013 Common Stock 9,247 (1) 0 D  
Option to buy (1) $ 15.825 02/24/2006   M     15,000 05/11/2005 04/28/2014 Common Stock 15,000 (1) 0 D  
Option to buy (1) $ 12.94 02/24/2006   M     15,000 05/18/2005 05/18/2015 Common Stock 15,000 (1) 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
KRONSER J ROBERT
55 JEWELERS PARK DRIVE
NEENAH, WI 54956
      Executive VP and CT&SO  

Signatures

 J. Robert Kronser, by Joseph D. Kaufman, Attorney-in-Fact   02/27/2006
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Options granted under the Plexus Corp. 2005 Equity Incentive Plan, or a predecessor plan, which qualifies under Rule 16b-3.
(2) Shares of Plexus Corp. common stock held in the Plexus Corp. Employee Stock Purchase Plan, as of December 31, 2005, the last date of a statement from the Plan's Trustee.

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