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

FORM 10-K/A
Amendment No. 1

(Mark One)

ý Annual report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

For the fiscal year ended December 31, 2001

or

o Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

For the transition period from                                      to                                     

Commission file number: 1-3562

AQUILA, INC. (formerly UtiliCorp United Inc.)
(Exact name of registrant as specified in its charter)

Delaware	44-0541877
State or other jurisdiction of incorporation or organization	(I.R.S. Employer Identification No.)

20 West Ninth Street, Kansas City, Missouri 64105
(Address of principal executive offices)

Registrant's telephone number, including area code (816) 421-6600

Securities registered pursuant to Section 12(b) of the Act:

Title of each class	Name of each exchange on which registered
Common Stock, par value $1.00 per share Convertible Subordinated Debentures, 65/8% due July 1, 2011	New York, Pacific and Toronto Stock Exchanges New York Stock Exchange
93/4% Premium Equity Participating Security Units, due November 16, 2004	New York Stock Exchange
7.875% Quarterly Interest Bonds, due March 1, 2032	New York Stock Exchange

Securities registered pursuant to Section 12(g) of the Act: None

        Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ý    No o

        Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. ý

        The aggregate market value of the voting stock held by non-affiliates of the Registrant, based upon the closing sale price of the Common Stock on March 15, 2002 as reported on the New York Stock Exchange, was approximately $3,268,452,000. Shares of Common Stock held by each officer and director and by each person who owns 5% or more of the outstanding Common Stock have been excluded in that such persons may be deemed to be affiliates. This determination of affiliate status is not necessarily a conclusive determination for other purposes.

Title	Outstanding (at March 15, 2002)
Common Stock, par value $1.00 per share	141,623,395
Documents Incorporated by Reference:	Where Incorporated:
2001 Annual Report to Shareholders	Part 2
Proxy Statement for 2002 Annual Shareholders Meeting	Part 3

INDEX

		Page
Item 8	Financial Statements and Supplementary Data	3
Part 4
Item 14	Exhibits, Financial Statement Schedules, and Reports on Form 8-K	3
Index to Exhibits		4
Signatures		5

2

Item 8. Financial Statements and Supplementary Data

        The information required by this item is incorporated by reference to pages 41 through 64 in our 2001 Annual Report to Shareholders.

        This Amendment No. 1 to Annual Report on Form 10-K is filed to correct the reversed placement of the captions "Electricity" and "Natural gas" under the headings "Sales" and "Cost of sales" on the Consolidated Statements of Income for the three years ended December 31, 2001 on page 41 of Exhibit 13, filed herewith.

Part 4

Item 14. Exhibits, Financial Statement Schedules, and Reports on Form 8-K

        The following documents are filed as part of this report:

(a)(1) Financial Statements:

	Page No.
Consolidated Statements of Income for the three years ended December 31, 2001	*
Consolidated Balance Sheets at December 31, 2001 and 2000	*
Consolidated Statements of Common Shareholders' Equity for the three years ended December 31, 2001	*
Consolidated Statements of Comprehensive Income for the three years ended December 31, 2001	*
Consolidated Statements of Cash Flows for the three years ended December 31, 2001	*
Notes to Consolidated Financial Statements	*
Report of Independent Public Accountants	*
* Incorporated by reference to pages 41 through 64 of our 2001 Annual Report to Shareholders.

3

AQUILA, INC.
INDEX TO EXHIBITS

Exhibit Number	Description
13	Annual Report to Shareholders for the year ended December 31, 2001.
23	Consent of Arthur Andersen LLP.

4

SIGNATURES

        Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized as of May 3, 2002.

Aquila, Inc.
By:	/s/  DAN STREEK Dan Streek Chief Financial Officer (Principal Financial and Accounting Officer)

5

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INDEX
Part 4
INDEX TO EXHIBITS
SIGNATURES