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

_________________

Date of Report  
(Date of earliest
event reported): December 1, 2004

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 1.01.    Entry into a Material Definitive Agreement.

        On December 1, 2004, the Compensation and Personnel Committee of the Board of Directors (the “Board”) of Alliant Energy Corporation, Interstate Power and Light Company and Wisconsin Power and Light Company (collectively, the “Company”) approved a form of Performance Contingent Restricted Stock Agreement under Alliant Energy Corporation’s 2002 Equity Incentive Plan (the “Plan”) and also approved grants of performance contingent restricted stock in shares of common stock of Alliant Energy Corporation, effective January 3, 2005, to certain executive officers of the Company under the Plan for which such form of Performance Contingent Restricted Stock Agreement will serve as the award agreement. The form of Performance Contingent Restricted Stock Agreement referred to above is filed as Exhibit 10.1 and is incorporated by reference herein.

        In addition, based on the recommendations of the Compensation and Personnel Committee and the Nominating and Governance Committee of the Board on December 1, 2004, the Board approved on December 2, 2004 modifications to the annual compensation for non-employee members of the Board, which will be as follows effective January 1, 2005:

  an $85,000 annual retainer for each non-employee director;
  a $15,000 annual retainer for the Lead Independent Director of the Board;
  a $10,000 annual retainer for the Chairperson of the Audit Committee of the Board;
  a $3,500 annual retainer for each member of the Audit Committee of the Board other than the Chairperson; and
  a $5,000 annual retainer for the Chairperson of each of the Compensation and Personnel Committee, the Nominating Committee and Governance Committee and the Nuclear, Health and Safety Committee of the Board.

A summary of compensation and benefits for non-employee members of the Board effective as of January 1, 2005 is filed as Exhibit 10.2 and is incorporated by reference herein.

Item 9.01.    Financial Statements and Exhibits.

  (a) Not applicable.

  (b) Not applicable.

  (c) Exhibits. The following exhibits are being filed herewith:

  (10.1) Form of Alliant Energy Corporation Performance Contingent Restricted Stock Award Agreement.

  (10.2) Summary of Compensation and Benefits for Non-Employee Directors of Alliant Energy Corporation, Interstate Power and Light Company and Wisconsin Power and Light Company, effective January 1, 2005.

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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

 
By:  /s/ John E. Kratchmer
Date:  December 7, 2004         John E. Kratchmer
        Vice President-Controller and
          Chief Accounting Officer


 
INTERSTATE POWER AND LIGHT COMPANY

 
By:  /s/ John E. Kratchmer
Date:  December 7, 2004         John E. Kratchmer
        Vice President-Controller and
        Chief Accounting Officer


 
WISCONSIN POWER AND LIGHT COMPANY

 
By:  /s/ John E. Kratchmer
Date:  December 7, 2004         John E. Kratchmer
        Vice President-Controller and
        Chief Accounting Officer






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ALLIANT ENERGY CORPORATION
INTERSTATE POWER AND LIGHT COMPANY
WISCONSIN POWER AND LIGHT COMPANY

Exhibit Index to Current Report on Form 8-K
Dated December 1, 2004

Exhibit
Number

(10.1) Form of Alliant Energy Corporation Performance Contingent Restricted Stock Agreement.

(10.2) Summary of Compensation and Benefits for Non-Employee Directors of Alliant Energy Corporation, Interstate Power and Light Company and Wisconsin Power and Light Company, effective January 1, 2005.











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