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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1. Name and Address of Reporting Person * DOYLE DUNDEANA K   2. Issuer Name and Ticker or Trading Symbol ALLIANT ENERGY CORP [LNT] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) VICE PRESIDENT (Last) (First) (Middle) PO BOX 2568 3. Date of Earliest Transaction (Month/Day/Year) 05/16/2006 (Street) MADISON, WI 53701 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 DRIP 05/16/2006   J(1)   3.6653 A $ 33.4817 432.257 D   401(k) 05/16/2006   P   193.4886 A $ 0 6,368.1168 D   COMMON IN STREET               580.47 D   COMMON (RESTRICTED) 05/16/2006   J(2)   27.1662 A $ 33.4817 3,192.6311 D

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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

DEFERRED COMMON STOCK

$ 0

05/17/2006

A(3)

57.2638

08/08/1988(4)

08/08/1988(4)

COMMON

57.2638

$ 33.7572

6,788.05

D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
DOYLE DUNDEANA K PO BOX 2568 MADISON, WI 53701			VICE PRESIDENT

Signatures

F. J. Buri as POA for		05/18/2006
**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)	The reporting person acquired 3.6653 shares under the company's dividend reinvestment plan, pursuant to a dividend reinvestment transaction exempt from Section 16 under Rule 16a-11.
(2)	The reporting person acquired 27.1662 shares under the company's dividend reinvestment plan, pursuant to a dividend reinvestment transaction exempt from Section 16 under Rule 16a-11.
(3)	The reporting person acquired 57.2638 shares under the company's dividend reinvestment plan, pursuant to a dividend reinvestment transaction exempt from Section 16 under Rule 16a-11.
(4)	Units are to be settled upon reporting person's retirement.

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