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UNITED STATES
SECURITIES AND EXCHANGE COMMISSIONWashington, D.C. 20549

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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

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

Delaware

44-0541877State 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 registeredCommon 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 Exchange93/4% Premium Equity Participating Security Units, due November 16, 2004

New York Stock Exchange7.875% Quarterly Interest Bonds, due March 1, 2032

New York Stock Exchange


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

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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                         

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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                                                               

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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.     

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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.                                    

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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:         

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