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

_________________

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of
the Securities Exchange Act of 1934

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Date of Report  
(Date of earliest
event reported): June 26, 2009

Commission Name of Registrant, State of Incorporation, Address of IRS Employer
File Number Principal Executive Offices and Telephone Number Identification Number

1-9894
Alliant Energy Corporation 39-1380265
(a Wisconsin corporation)
4902 N. Biltmore Lane
Madison, Wisconsin 53718
Telephone (608) 458-3311

0-4117-1
Interstate Power and Light Company 42-0331370
(an Iowa corporation)
Alliant Energy Tower
Cedar Rapids, Iowa 52401
Telephone (319) 786-4411

0-337
Wisconsin Power and Light Company 39-0714890
(a Wisconsin corporation)
4902 N. Biltmore Lane
Madison, Wisconsin 53718
Telephone (608) 458-3311

This combined Form 8-K is separately filed by Alliant Energy Corporation, Interstate Power and Light Company and Wisconsin Power and Light Company.

_________________

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

[   ] Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
[   ] Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
[   ] Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
[   ] Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))


Item 5.02. Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

        (b)        On June 26, 2009, James A. Leach informed the Chairman of the Boards of Directors (the “Boards”) of Alliant Energy Corporation, Interstate Power and Light Company and Wisconsin Power and Light Company that he will be required to resign from the Boards effective upon his confirmation to the post of Chairman of the National Endowment of the Humanities. Mr. Leach’s confirmation is anticipated to occur before August 2009.









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SIGNATURES

        Pursuant to the requirements of the Securities Exchange Act of 1934, Alliant Energy Corporation, Interstate Power and Light Company and Wisconsin Power and Light Company have each duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

ALLIANT ENERGY CORPORATION

Date:   June 29, 2009
By:  /s/ Barbara J. Swan
        Barbara J. Swan
        Executive Vice President-General Counsel
          and Chief Administrative Officer

 
INTERSTATE POWER AND LIGHT COMPANY

Date:  June 29, 2009
By:  /s/ Barbara J. Swan
        Barbara J. Swan
        Executive Vice President-General Counsel
          and Chief Administrative Officer

 
WISCONSIN POWER AND LIGHT COMPANY

Date:  June 29, 2009
By:  /s/ Barbara J. Swan
        Barbara J. Swan
        President




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