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UNITED STATESSECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

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FORM 10-Q

|                                                                     | x | QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15 (d)OF THE SECURITIES EXCHANGE ACT OF 1934  | 
|-------------------------------------------------------------------- | - | ---------------------------------------------------------------------------------------- | 
|                                                                    
|For the quarterly period ended June 30, 2002                        
|                                                                    
|                                                                     | 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 000-23783                                    
|                                                                    
|                                                                    
|MICROMUSE INC.(Exact name of registrant as specified in its charter)

|                                                              |                                  
|------------------------------------------------------------- | ---------------------------------
|DELAWARE                                                      | 94-3288385                       
|                                                              |                                  
|(State or other jurisdiction ofincorporation or organization) | (IRS Employer Identification No.)
|                                                              |                                  

139 TOWNSEND STREETSAN FRANCISCO, CALIFORNIA 94107(415) 538-9090(Address, including ZIP
code, and telephone number)

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   x     No  o

74,737,662 shares of Common Stock, $0.01 par
value, were outstanding as of July 31, 2002.

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MICROMUSE INC.

TABLE OF CONTENTS

|                                |                                                                                                            |     
|------------------------------- | ---------------------------------------------------------------------------------------------------------- | ----
|                                |                                                                                                            | Page
|PART  I - Financial Information
|                                |                                                                                                            |     
|Item 1.                         | Condensed Consolidated Financial Statements:                                                               |     
|                                |                                                                                                            |     
|                                | Condensed Consolidated Balance Sheets as of June 30, 2002 and September 30, 2001                           | 3   
|                                |                                                                                                            |     
|                                | Condensed Consolidated Statements of Operations for the three and nine months ended June 30, 2002 and 2001 | 4   
|                                |                                                                                                            |     
|                                | Condensed Consolidated Statements of Cash Flows for the nine months ended June 30, 2002 and 2001           | 5   
|                                |                                                                                                            |     
|                                | Notes to Condensed Consolidated Financial Statements                                                       | 6   
|                                |                                                                                                            |     
|                                |                                                                                                            |     
|Item 2.                         | Management's Discussion and Analysis of Financial Condition and Results of Operations                      | 10  
|                                |                                                                                                            |     
|                                |                                                                                                            |     
|Item 3.                         | Quantitative and Qualitative Disclosures about Market Risk                                                 | 30  
|                                |                                                                                                            |     
|                                |                                                                                                            |     
|                                |                                                                                                            |     
|PART  II - Other Information   
|                                |                                                                                                            |     
|Item 1.                         | Legal Proceedings                                                                                          | 31  
|                                |                                                                                                            |     
|Item 2.                         | Changes in Securities and Use of Proceeds                                                                  | 31  
|                                |                                                                                                            |     
|Item 3.                         | Defaults upon Senior Securities                                                                            | 31  
|                                |                                                                                                            |     
|Item 4.                         | Submission of Matters to a Vote of Security Holders                                                        | 31  
|                                |                                                                                                            |     
|Item 5.                         | Other Information                                                                                          | 31  
|                                |                                                                                                            |     
|Item 6.                         | Exhibits and Reports on Form 8-K                                                                           | 32  
|                                |                                                                                                            |     
|Signatures                      | 33                                                                                                        
|                                |                                                                                                            |     

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Part I  FINANCIAL INFORMATIONItem 1. Condensed Consolidated Financial Statements

MICROMUSE INC.

CONDENSED CONSOLIDATED BALANCE SHEETS(In thousands, except per share data)(Unaudited)

|ASSETS                                                                   
|-------------------------------------------------------------------------
|                                                                         
|                                                                         
|                                                                         
|Current assets:                                                          
|Cash and cash equivalents                                                
|Short-term investments                                                   
|Billed receivables, net                                                  
|Prepaid expenses and other current assets                                
|                                                                         
|Total current assets                                                     
|                                                                         
|Property and equipment, net                                              
|Long-term investments                                                    
|Goodwill and other intangible assets, net                                
|                                                                         
|                                                                         
|                                                                         
|                                                                         
|LIABILITIES AND STOCKHOLDERS' EQUITY                                     
|                                                                         
|Current liabilities:                                                     
|Accounts payable                                                         
|Accrued expenses                                                         
|Income taxes payable                                                     
|Deferred revenue                                                         
|                                                                         
|Total current liabilities                                                
|                                                                         
|Stockholders' equity                                                     
|Preferred stock; $0.01 par value; 5,000 shares authorized;               
|no shares issued and outstanding                                         
|Common stock; $0.01 par value; 200,000 shares authorized;                
|74,730 and 73,903 shares outstanding as of June 30,                      
|2002 and September 30, 2001, respectively                                
|Additional paidin capital                                               
|Treasury stock                                                           
|Accumulated other comprehensive loss                                     
|Retained earnings                                                        
|                                                                         
|Total stockholders' equity                                               
|                                                                         
|                                                                         
|                                                                         
|                                                                         
|See accompanying notes to the condensed consolidated financial statements

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|MICROMUSE INC.                                                           
|-------------------------------------------------------------------------
|CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS                          
|(In thousands, except per share data)                                    
|(Unaudited)                                                              
|                                                                         
|                                                                         
|                                                                         
|                                                                         
|                                                                         
|                                                                         
|Revenues:                                                                
|License                                                                  
|Maintenance and services                                                 
|                                                                         
|Total revenues                                                           
|                                                                         
|                                                                         
|Cost of revenues:                                                        
|License                                                                  
|Maintenance and services                                                 
|                                                                         
|Total cost of revenues                                                   
|                                                                         
|Gross profit                                                             
|                                                                         
|                                                                         
|Operating expenses:                                                      
|Sales and marketing                                                      
|Research and development                                                 
|General and administrative                                               
|Amortization of goodwill and other intangible assets                     
|Executive recruiting costs                                               
|                                                                         
|Total operating expenses                                                 
|                                                                         
|Income (loss) from operations                                            
|                                                                         
|Other income, net                                                        
|                                                                         
|Income (loss) before income taxes                                        
|Income tax provision (benefit)                                           
|                                                                         
|Net income (loss)                                                        
|                                                                         
|                                                                         
|                                                                         
|Per share data:                                                          
|Basic net income (loss)                                                  
|Diluted net income (loss)                                                
|                                                                         
|Weighted average shares used in computing:                               
|Basic net income (loss) per share                                        
|Diluted net income (loss) per share                                      
|                                                                         
|                                                                         
|See accompanying notes to the condensed consolidated financial statements

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MICROMUSE INC.

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS(In thousands)(Unaudited)

|                                                                                  | Nine months ended |          
|--------------------------------------------------------------------------------- | ----------------- | ---------
|                                                                                  | June 30,          |          
|                                                                                  |                   |          
|                                                                                  | 2002              |          
|                                                                                  |                   |          
|Cash flows from operating activities:                                             |                   |          
|Net income                                                                        | $                 | 56       
|Adjustments to reconcile net income to net cash provided by operating activities: |                   |          
|Depreciation and amortization                                                     |                   | 15,089   
|Amortization of deferred employee compensation                                    |                   | -        
|Compensation expense related to issuance of warrant                               |                   | 170      
|Tax benefit related to exercise of stock options                                  |                   | 56       
|Deferred income taxes                                                             |                   | -        
|Changes in operating assets and liabilities:                                      |                   |          
|Billed receivables, net                                                           |                   | 8,207    
|Prepaid expenses and other current assets                                         |                   | 5,550    
|Accounts payable                                                                  |                   | (4,430   
|Accrued expenses                                                                  |                   | (11,628  
|Income taxes payable                                                              |                   | (13      
|Deferred revenue                                                                  |                   | 4,226    
|                                                                                  |                   |          
|Net cash provided by operating activities                                         |                   | 17,283   
|                                                                                  |                   |          
|                                                                                  |                   |          
|Cash flows from investing activities:                                             |                   |          
|Capital expenditures                                                              |                   | (2,450   
|Investment purchases, net                                                         |                   | (46,685  
|                                                                                  |                   |          
|Cash used in investing activities                                                 |                   | (49,135  
|                                                                                  |                   |          
|                                                                                  |                   |          
|Cash flows from financing activities:                                             |                   |          
|Proceeds from issuance of common stock                                            |                   | 4,888    
|                                                                                  |                   |          
|Net cash provided by financing activities                                         |                   | 4,888    
|                                                                                  |                   |          
|Effects of exchange rate changes on cash and cash equivalents                     |                   | (945     
|                                                                                  |                   |          
|Net increase (decrease) in cash and cash equivalents                              |                   | (27,909  
|Cash and cash equivalents at beginning of period                                  |                   | 138,581  
|                                                                                  |                   |          
|Cash and cash equivalents at end of period                                        |                   | $ 110,672
|                                                                                  |                   |          

See accompanying notes to the condensed consolidated financial statements

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MICROMUSE INC.

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

Note 1.  Basis of Presentation

The condensed consolidated financial statements are the unaudited historical financial statements of Micromuse Inc. and subsidiaries (the Company) and reflect all adjustments (consisting only of normal recurring adjustments)
that, in the opinion of management, are necessary for a fair presentation of interim period results. These condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto
included in the Companys Form 10-K as filed with the Securities and Exchange Commission on December 21, 2001. The September 30, 2001, consolidated balance sheet included herein was derived from audited financial statements, but does not
include all disclosures, including notes, required by generally accepted accounting principles.

The results of operations for the current interim period are not necessarily indicative
of results to be expected for the entire current year or other future interim periods.

ReclassificationsCertain
reclassifications, none of which affected net income, have been made to prior amounts to conform to the current period presentation.

Use of EstimatesThe preparation of condensed consolidated financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period.
Actual results could differ from these estimates.

Cash EquivalentsThe Company considers all highly liquid instruments with a
maturity at purchase of three months or less to be cash equivalents.

Shareholders Equity and Stock SplitAll share and
per-share numbers herein reflect the 2 for 1 stock split of our common stock that occurred for stockholders of record on December 5, 2000.

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MICROMUSE INC.

Per Share DataBasic per share amounts are calculated using the weighted-average number of common shares outstanding during the period. Diluted per share amounts are calculated using the weighted-average number of common shares outstanding during the
period and, when dilutive, the weighted-average number of potential common shares from the exercise of outstanding options and warrants to purchase common stock using the treasury stock method. Excluded from the computation of net loss per share for
the three months ended June 30, 2002, was a warrant to acquire 54,321 shares of common stock at $5.42 per share, and options to acquire approximately 12.6 million shares of common stock, with a weighted average exercise price of $23.18 per share,
because their effect would be anti-dilutive. A reconciliation of the numerators and denominators used in the basic and diluted net income per share amounts follows (in thousands):

|                                                                                        | Three months ended |        | Nine months ended
|--------------------------------------------------------------------------------------- | ------------------ | ------ | -----------------
|                                                                                        | June 30,           |        | June 30,         
|                                                                                        |                    |        |                  
|                                                                                        | 2002               |        |                  
|                                                                                        |                    |        |                  
|                                                                                        |                    |        |                  
|Numerator for basic and diluted net income (loss)                                       | $                  | (979   | )                
|                                                                                        |                    |        |                  
|Denominator for basic net income (loss) per share  weighted-average shares outstanding |                    | 74,711 |                  
|Dilutive effect of:                                                                     |                    |        |                  
|Common stock options                                                                    |                    | -      |                  
|Warrant                                                                                 |                    | -      |                  
|                                                                                        |                    |        |                  
|Denominator for diluted net income per share                                            |                    | 74,711 |                  
|                                                                                        |                    |        |                  

As of June 30, 2002 and 2001, there were approximately 12.6 million and 12.0 million options outstanding,
respectively.

Concentration of RevenuesOne third-party distributor customer accounted for 13% of revenue for the quarter ended
June 30, 2002. Another third-party distributor accounted for approximately 16% and 13% of revenues for the nine months ended June 30, 2002 and 2001, respectively, and 17% of revenues for the quarter ended June 30, 2001. One end-user customer
accounted for approximately 22% of revenues for the quarter ended June 30, 2002, and another end-user customer accounted for 19% of revenues for the quarter ended June 30, 2001. No one end-user customer accounted for greater than 10% of revenues for
the nine months ended June 30, 2002 and 2001.

Accounts ReceivableAccounts Receivable includes an allowance for doubtful accounts
of $4.2 million as of June 30, 2002 and September 30, 2001.

Accumulated Other Comprehensive LossThe only component of
accumulated other comprehensive loss is net foreign currency translation adjustments. Other comprehensive income for the quarter ended June 30, 2002 and 2001, was $121,000 and $84,000, respectively. Other comprehensive loss for the nine months ended
June 30, 2002 was $862,000 as compared to income of $80,000 for the nine months ended June 30, 2001.

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MICROMUSE INC.

Geographic and Segment InformationThe Companys chief
operating decision-maker is considered to be the Companys Chief Executive Officer (CEO). The CEO reviews financial information presented on a consolidated basis accompanied by certain geographic information for purposes of making
operating decisions and assessing financial performance. Therefore, the Company operates as a single operating segment: service and business assurance software.

The Company markets its
products primarily from the United States. International sales are primarily to customers in the United Kingdom and continental Europe. Information regarding regional revenues, which are based on the location of the end-user, and operations in
different geographic regions is as follows (in thousands):

|                     | Three months ended |          | Nine months ended
|-------------------- | ------------------ | -------- | -----------------
|                     | June 30,           |          | June 30,         
|                     |                    |          |                  
|                     | 2002               |          | 2001             
|                     |                    |          |                  
|Revenues:            |                    |          |                  
|United States        | $                  | 17,473   |                  
|United Kingdom       |                    | 2,578    |                  
|International        |                    | 14,983   |                  
|                     |                    |          |                  
|Total                | $                  | 35,034   |                  
|                     |                    |          |                  
|                     |                    |          |                  
|                     | June 30,           |          | September 30,    
|                     | 2002               |          | 2001             
|                     |                    |          |                  
|Long - lived assets: |                    |          |                  
|United States        |                    | $ 34,824 |                  
|International        |                    | 4,010    |                  
|                     |                    |          |                  
|Total                |                    | $ 38,834 |                  
|                     |                    |          |                  

Subsequent Events On June 19, 2002, the Company commenced a cash tender offer to acquire all of the issued
and to be issued share capital of RiverSoft plc for Stg £0.1775 per share ($0.275 per share), (the Offer). The Offer values the entire issued share capital of RiverSoft at approximately Stg £43.3 ($67.1) million. On July 24,
2002, the Company announced the first closing date of the recommended cash offer, in which valid acceptances of the Offer had been received in respect of 221,746,021 RiverSoft shares, representing in aggregate approximately 90.8% of RiverSoft's
total issued share capital. On August 6, 2002, the Company paid cash consideration of Stg £41.4 ($64.2) million to shareholders who had accepted the offer in exchange for their issued shares. The Company has also issued formal notices under
section 429 of the Companies Act 1985 (U.K.) to acquire compulsorily all those RiverSoft ordinary shares in respect of which valid acceptances have not been received.

On July 25, 2002,
Micromuse agreed to a partial termination of a contract that was recorded as revenue in the quarter ended June 30, 2002, in accordance with Statement of Position 97-2, Software Revenue Recognition. The contract did not have a termination
provision and at June 30, 2002, the fee was fixed and determinable. As a result, approximately $2.5 million will be accounted for as a negative adjustment to revenue in the quarter ended September 30, 2002.

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MICROMUSE INC.

Recent PronouncementsIn July
2001, the Financial Accounting Standards Board (FASB) issued Statement of Financial Accounting Standards (SFAS) No. 141, Business Combinations. Under SFAS No. 141, entities are required to account for all business combinations initiated after
June 30, 2001 using one method, the purchase method. SFAS No. 141 also requires that an intangible asset acquired in a business combination be recognized apart from goodwill if (i) the intangible asset arises from contractual or other legal rights
or (ii) the acquired intangible is capable of being separated from the acquired enterprise, as defined in SFAS No. 141. The Company adopted SFAS No. 141 on July 1, 2001. The adoption did not have an effect on the Companys consolidated
financial position or results of operations.

In July 2001, the FASB issued SFAS No. 142, Goodwill and Other Intangible Assets. SFAS No. 142 addresses financial accounting and reporting for
acquired goodwill and other intangible assets. SFAS No. 142 changes the accounting for goodwill from an amortization method to an impairment-only approach. Goodwill will be tested annually and whenever events or circumstances occur indicating that
goodwill might be impaired. Upon adoption of SFAS No. 142, amortization of goodwill recorded for business combinations consummated prior to July 1, 2001 will cease, and intangible assets acquired prior to July 1, 2001 that do not meet the criteria
for recognition under SFAS No. 141 will be reclassified to goodwill. Companies are required to adopt SFAS No. 142 for fiscal years beginning after December 15, 2001, but early adoption is permitted. The Company will adopt SFAS No. 142 on October 1,
2002. Upon adoption, approximately $16.4 million of goodwill will no longer be amortized but will be tested annually for impairment.

In October 2001, the FASB issued SFAS No. 144, Accounting for
the Impairment or Disposal of Long-Lived Assets, which is effective for fiscal years beginning after December 15, 2001 and early adoption is permitted. SFAS No. 144 supersedes certain provisions of APB Opinion No. 30 Reporting the
Results of Operations-Reporting the Effects of Disposal of a Segment of a Business, and Extraordinary, Unusual and Infrequently Occurring Events and Transactions (APB 30) and supersedes SFAS No. 121 Accounting for the Impairment of Long-Lived
Assets and for Long-Lived Assets to Be Disposed Of. Although SFAS No. 144 supersedes SFAS No. 121 and the provisions of APB 30 regarding the accounting and reporting of the disposal of a segment of a business, it retains many of the fundamental
provisions of SFAS No. 121 and the requirements in APB 30 to report separately discontinued operations. SFAS No. 144 also extends the reporting of discontinued operations to a component of an entity that either has been disposed of (by sale,
abandonment, or in a distribution to owners) or is classified as held for sale. The Company will adopt SFAS No. 144 on October 1, 2002 and does not expect that adoption will have a material effect on its consolidated financial position, results of
operations, or cash flows.

In November 2001, the Emerging Issues Task Force (EITF) reached consensus on EITF No. 01-9, Accounting for Consideration Given by a Vendor to a Customer or a Reseller
of the Vendors Products. EITF No. 01-9 addresses the accounting for consideration given by a vendor to a customer and is a codification of EITF No. 00-14, Accounting for Certain Sales Incentives, EITF No. 00-22, Accounting for
Points and Certain Other Time-Based or Volume-Based Sales Incentives Offers and Offers for Free Products or Services to be Delivered in the Future, and EITF No. 00-25, Vendor Income Statement Characterization of Consideration Paid
to a Reseller of the Vendors Products. The Company adopted EITF No. 01-9 in the quarter ending March 31, 2002 and it did not have an effect on the Companys financial position and results of operations.

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MICROMUSE INC.

Item 2. Managements Discussion and Analysis of Financial Condition and Results of Operations

The following information should be read in conjunction with the
condensed consolidated historical financial information and the notes thereto included in Item 1 of this Quarterly Report on Form 10-Q and Managements Discussion and Analysis of Financial Condition and Results of Operations contained in our
Form 10-K as filed with the Securities and Exchange Commission on December 21, 2001.

The statements contained in this Form 10-Q that are not purely historical are forward-looking statements within
the meaning of Section 21E of the Securities Exchange Act of 1934, including statements regarding our expectations, beliefs, hopes, intentions or strategies regarding the future. All forward-looking statements in this Form 10-Q are based upon
information available to us as of the date hereof, and we assume no obligation to update any such forward-looking statements. Actual results could differ materially from our current expectations. Factors that could cause or contribute to such
differences include, but are not limited to: variation in demand for our software products and services; the level and timing of sales; the extent of product and price competition; introductions or enhancements of products or delays in introductions
or enhancements of products; hiring and retention of personnel; changes in the mix of products and services sold; general domestic and international economic and political conditions; and other factors and risks discussed in Risk Factors
below and elsewhere in this Quarterly Report, and other Micromuse filings with the Securities and Exchange Commission.

OverviewMicromuse Inc. develops, markets and supports a
family of scalable, highly configurable, rapidly deployable software solutions that enable realtime fault management and service assurance  the effective monitoring and management of multiple elements underlying an Information Technology
infrastructure, including network devices, computing systems and applications, and the mapping of these elements to the business services they impact.

Micromuse Ltd (formerly known as Micromuse
plc) was incorporated in England in 1989 and in March 1997 became a subsidiary of Micromuse Inc., a Delaware corporation formed in connection with a corporate reorganization and relocation of the corporate headquarters to San Francisco, California.
As used herein, the term Micromuse or the Company refers to Micromuse Inc., Micromuse Ltd, and their other subsidiaries, unless the context otherwise requires or unless otherwise expressly stated. Our principal executive
offices are located at 139 Townsend Street, San Francisco, California 94107, and our telephone number at that address is (415) 538-9090.

Critical Accounting Policies and
EstimatesOur discussion and analysis of our financial condition and results of operations are based upon our condensed consolidated financial statements, which have been prepared in
accordance with accounting principles generally accepted in the United States. The preparation of these financial statements requires us to make estimates and judgments that affect the reported amounts of assets, liabilities, revenues and expenses,
and related disclosure of contingent assets and liabilities. On an on-going basis, we evaluate our estimates, including, but not limited to, revenue recognition, bad debts, warranty obligations, investments, intangible assets, income taxes,
contingencies and litigation. We base our estimates on historical experience and on various other assumptions that we believe to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying
values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions.

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MICROMUSE INC.

We believe the following are the critical accounting policies and estimates that are
used in the preparation of its consolidated financial statements:

Revenue Recognition. Our revenues are derived from license revenues for our Netcool family of products, as well as
associated maintenance, consulting and training services revenues. We recognize revenue in accordance with Statement of Position 97-2, Software Revenue Recognition (SOP 97-2), as amended by SOP 98-9, Software Revenue Recognition with
Respect to Certain Arrangements, and recognize revenue using the residual method. Under the residual method, revenue is recognized when Company-specific objective evidence of fair value exists for all of the undelivered elements in the
arrangement (i.e., maintenance and professional services), but does not exist for one or more of the delivered elements in the arrangement (i.e., the software product). We allocate revenue to each undelivered element based on its respective fair
value, with the fair value determined by the price charged when that element is sold separately. We determine the fair value of the maintenance portion of the arrangement to be based on the renewal price charged to the customer when maintenance is
sold separately or the option price for annual maintenance renewals included in the underlying customer contracts. The fair value of the professional services portion of the arrangement is based on the hourly rates that we charge for these services
when sold independently from a software license. At the outset of the arrangement with the customer, we defer revenue for the fair value of the undelivered elements and recognize revenue for the delivered elements when the basic criteria of SOP 97-2
have been met. If evidence of fair value cannot be established for the undelivered elements of a license agreement, the entire amount of revenue from the arrangement is deferred and recognized over the period that these elements are
delivered.

For all of our software arrangements, we defer revenue for the fair value of the undelivered elements and recognize revenue for the delivered elements when the basic criteria of SOP 97-2
have been met - (1) persuasive evidence of an arrangement exists, (2) delivery has occurred, (3) the vendors fee is fixed or determinable and (4) collectibility is probable. We evaluate each as follows:

|- | Persuasive evidence of an arrangement exists: For license arrangements with end-users, an arrangement is evidence by a written contract, which is signed by both the customer and us, or a purchase order from
those customers who have previously negotiated a standard license arrangement with us. Sales to our resellers are evidenced by a master agreement governing the relationship together with a purchase order on a transaction-by-transaction basis. For
certain of our OEM arrangements, an arrangement is evidenced on receipt of a delivery notification to the end user.
|- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| 
|- | Delivery has occurred: Delivery is considered to have occurred when media containing the licensed programs is provided to a common carrier or, in the case of electronic delivery, the customer is given access
to the licensed programs. In the case of arrangements with resellers and OEMs, revenue is recognized upon sell-through. Evidence of sell-through usually comes in the form of a purchase order or contract identifying the end-user and
sell-through shipping reports, usually identifying the ship to location.                                                      
| 
|- | Fixed or determinable fee: We consider the fee to be fixed or determinable if the fee is not subject to refund or adjustment. If the arrangement fee is not fixed or determinable, the Company recognizes the
revenue as amounts become due and payable.                                                                                                                                                                                                                                                                                                                                 
| 
|- | Collection is probable: We conduct a credit review for all significant transactions at the time of the arrangement to determine the creditworthiness of the customer. Collection is deemed probable if we
expect that the customer will be able to pay amounts under the arrangement as payments                                                                                                                                                                                                                                                                                         

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MICROMUSE INC.

| | become due. If we determine that collection is not probable, we defer the revenue and recognize the revenue upon cash collection.
| | ---------------------------------------------------------------------------------------------------------------------------------

Maintenance revenues from ongoing customer support and product upgrades are deferred and recognized ratably over the term of the maintenance agreement, typically 12 months. Payments for maintenance fees (on initial order or on renewal) are
generally made in advance and are nonrefundable. Revenues for professional services are recognized as the services are performed. Professional services generally are not essential to the functionality of the software. Our software products are fully
functional upon delivery and do not require any significant modification or alteration.

Deferred revenue includes revenue not yet recognized as a result of deferred maintenance, professional
services not yet rendered and license revenue deferred until all the requirements of SOP 97-2 are met.

Provision for Doubtful accounts. We maintain allowances for doubtful accounts for
estimated losses resulting from the inability of our customers to make required payments. In estimating the provision for doubtful accounts, management considers the age of the accounts receivable, the our historical write-offs, the creditworthiness
of the customer, the economic conditions of the customers industry, and general economic conditions, among other factors. Should any of these factors change, the estimates made by management will also change, which could impact the level of
our future provision for doubtful accounts. Specifically, if the financial condition of our customers were to deteriorate, resulting in an impairment of their ability to make payments, additional allowances may be required.

Goodwill and other intangible assets. We regularly perform reviews to determine if the carrying value of goodwill and other intangible assets are impaired. The purpose of the review is to identify any facts or
circumstances, either internal or external, which indicate that the carrying value of the asset cannot be recovered. If management determines an indicator of impairment, under the current policy, we would use undiscounted cash flows to initially
determine whether impairment should be recognized. If necessary, we would perform a subsequent calculation to measure the amount of the impairment loss based on the excess of the carrying value over the fair value of the impaired assets. If quoted
market prices for the assets are not available, the fair value would be calculated using the present value of estimated expected future cash flows. The cash flow calculation would be based on managements best estimates, using appropriate
assumptions and projections at the time.

Pro Forma Financial ResultsWe prepare and release quarterly unaudited financial statements
prepared in accordance with generally accepted accounting principles (GAAP). We also disclose and discuss certain pro forma financial information in the related earnings release and investor conference call. This pro forma financial
information excludes certain non-cash and special charges, consisting primarily of the amortization of goodwill and other intangible assets and executive recruiting costs. We believe the disclosure of the pro forma financial information helps
investors more meaningfully evaluate the results of our ongoing operations. However, we urge investors to carefully review the GAAP financial information included as part of our Quarterly Reports on Form 10-Q, our Annual Reports on Form 10-K, and
our quarterly earnings releases.

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Results of OperationsThe following table sets forth certain items in our consolidated statement of operations as a percentage of total revenues, except as indicated:

|                                                     |  | Three months ended |   | Nine months ended
|---------------------------------------------------- |  | ------------------ | - | -----------------
|                                                     |  | June 30,           |   | June 30,         
|As a Percentage of Total Revenues:                   |  | 2002               |   | 2001             
|                                                     |  |                    |   |                  
|Revenues:                                            |  |                    |   |                  
|License                                              |  | 57.3               | % |                  
|Maintenance and services                             |  | 42.7               | % |                  
|                                                     |  |                    |   |                  
|Total revenues                                       |  | 100.0              | % |                  
|                                                     |  |                    |   |                  
|                                                     |  |                    |   |                  
|Cost of revenues:                                    |  |                    |   |                  
|License                                              |  | 4.5                | % |                  
|Maintenance and services                             |  | 11.7               | % |                  
|                                                     |  |                    |   |                  
|Total cost of revenues                               |  | 16.2               | % |                  
|                                                     |  |                    |   |                  
|Gross profit                                         |  | 83.8               | % |                  
|                                                     |  |                    |   |                  
|                                                     |  |                    |   |                  
|Operating expenses:                                  |  |                    |   |                  
|Sales and marketing                                  |  | 51.0               | % |                  
|Research and development                             |  | 23.6               | % |                  
|General and administrative                           |  | 11.7               | % |                  
|Amortization of goodwill and other intangible assets |  | 7.9                | % |                  
|Executive recruiting costs                           |  | 0.0                | % |                  
|                                                     |  |                    |   |                  
|Total operating expenses                             |  | 94.2               | % |                  
|                                                     |  |                    |   |                  
|Income (loss) from operations                        |  | (10.4              | % | )                
|                                                     |  |                    |   |                  
|Other income, net                                    |  | 4.1                | % |                  
|                                                     |  |                    |   |                  
|Income before income taxes                           |  | (6.3               | % | )                
|Income tax provision                                 |  | (3.5               | % | )                
|                                                     |  |                    |   |                  
|Net income                                           |  | (2.8               | % | )                
|                                                     |  |                    |   |                  
|                                                     |  |                    |   |                  
|As a Percentage of Related Revenues:                 |  |                    |   |                  
|                                                     |  |                    |   |                  
|Cost of license revenues                             |  | 7.8                | % |                  
|Cost of maintenance and services revenues            |  | 27.6               | % |                  

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Revenues. Revenues decreased to $35.0 million and $114.1 million in
the quarter and nine months ended June 30, 2002, from $63.3 million and $172.5 million in the comparable periods of the prior year. License revenues decreased to $20.1 million and $67.9 million in the quarter and nine months ended June 30, 2002,
from $46.4 million and $126.0 million in the comparable periods of the prior year. The decline in license revenues was primarily due to the current economic slowdown that is limiting the overall capital spending of our existing and potential
customers. Maintenance and services revenues were $15.0 million and $46.2 million in the quarter and nine months ended June 30, 2002, as compared to $16.9 million and $46.5 million in the comparable periods of the prior year. The decrease in
maintenance and services revenues was mainly a result of lower overall services revenue. License revenues as a percentage of total revenues were 57.3% and 59.5% in the quarter and nine months ended June 30, 2002, as compared to 73.3% and 73.0% in
the comparable periods of the prior year.

On July 25, 2002, Micromuse agreed to a partial termination of a contract that was recorded as revenue in the quarter ended June 30, 2002, in
accordance with Statement of Position 97-2, Software Revenue Recognition. The contract did not have a termination provision and at June 30, 2002, the fee was fixed and determinable. As a result, approximately $2.5 million will be accounted
for as a negative adjustment to revenue in the quarter ended September 30, 2002.

Cost of Revenues. The cost of license revenues consists primarily of technology license fees
paid to third-party software vendors and production costs. Cost of license revenues as a percentage of license revenues increased to 7.8% and 6.9% in the quarter and nine months ended June 30, 2002, as compared to 5.5% and 5.6% in the comparable
periods of the prior year. The increase was mainly due to a change in the mix of license revenue and the effect of the amortization of a time based royalty on decreased license revenue. The cost of maintenance and services revenues consists
primarily of personnel-related costs incurred in providing maintenance, consulting and training to customers. Cost of maintenance and services revenues as a percentage of maintenance and services revenues decreased to 27.6% and 30.2% in the quarter
and nine months ended June 30, 2002, from 43.1% and 42.0% in the comparable periods of the prior year. This improvement, which was principally due to a proportionally greater percentage of higher-margin maintenance revenues and economies of scale,
was partially offset by increased personnel, facilities, and travel costs associated with expanding the customer support and technical service organizations.

Sales and Marketing
Expenses. Sales and marketing expenses decreased to $17.9 million and $54.0 million in the quarter and nine months ended June 30, 2002, from $26.0 million and $72.2 million in the comparable periods of the prior year. This decrease was primarily
due to the related decrease in revenueand a decrease in personnel related costs as a result of lower headcount and travel expenditure.. Sales and marketing expenses as a percentage of total revenues increased to 51.0% and 47.4% in the quarter and
nine months ended June 30, 2002, from 41.0% and 41.8% in the comparable periods of the prior year.

Research and Development Expenses. Research and development expenses decreased
to $8.3 million and $23.9 million in the quarter and nine months ended June 30, 2002, from $9.3 million and $26.2 million in the comparable periods of the prior year. The decrease was mainly due to decreases in headcount and travel related
expenditures. Research and development costs as a percentage of total revenues have increased to 23.6% and 20.9% in the quarter and nine months ended June 30, 2002, as compared to 14.6% and 15.2% in the same periods of the prior year.

General and Administrative Expenses. General and administrative expenses decreased to $4.1 million and $13.1 million in the quarter and nine months ended June 30, 2002, from $5.8 million and
$14.9 million in the comparable periods of the prior year. The decrease in the quarter ended June 30, 2002 as

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compared to the prior year period, was primarily due to a decrease in
headcount. . The decrease in the nine months ended June 30, 2002 as compared to the prior year period, was mainly due to a decrease in headcount but was offset by a bad debt reserve related to Global Crossing, which was recorded in the quarter ended
December 31, 2001. Global Crossing filed for Chapter 11 bankruptcy protection in January 2002. However, Global Crossing has continued to make payments in accordance with the terms of the agreement and management believes that the Company is
adequately reserved at June 30, 2002 for this customer. As of the date of this filing, the Company had an immaterial exposure to this customer.

General and administrative expenses as a
percentage of revenues have increased to 11.7% and 11.5% in the quarter and nine months ended June 30, 2002, from 9.2% and 8.7% in the comparable periods of the prior year.

Amortization of Goodwill and Other Intangible Assets. The charge of $2.8 million and $8.3 million in the quarter and nine months ended June 30, 2002 and 2001, reflects the amortization of the goodwill and other intangible assets over
estimated useful lives of three to five years.

Executive Recruiting Costs. The executive recruiting costs of $0.4 million in the nine months ended June 30, 2002 are primarily
costs incurred in the recruitment of a new Chief Financial Officer. The costs relate to the fair value of a warrant issued to an executive recruiting firm, fees paid to the recruiting firm and certain relocation costs.

Other Income, Net. Other income decreased to $1.5 million and $4.4 million in the quarter and nine months ended June 30, 2002, from $1.9 million and $5.6 million in the comparable periods of
the prior year. This net decrease was primarily due to the decline in interest rates over the past year.

Provision for Income Taxes. Income taxes showed a benefit
of $1.2 million and a charge of $0.0 million in the quarter and nine months ended June 30, 2002, as compared to $3.7 million and $9.6 million in the comparable periods of the prior year. The overall decrease was mainly due to the related decline in
taxable income. The benefit in the quarter reflects lower earnings for the period as compared to original annual projections.

Liquidity and Capital ResourcesAs of
June 30, 2002, we had $110.7 million in cash and cash equivalents and $83.7 million in marketable securities, as compared to $138.6 million in cash and cash equivalents and $37.0 million in marketable securities as of September 30, 2001. The net
decrease in cash and cash equivalents in the nine months ended June 30, 2002, was due primarily to the purchase of marketable securities, capital expenditures and the decrease in accounts payable and accrued expenses. These outflows of cash and cash
equivalents were partially offset by net income adjusted for non-cash expenses, the decrease in billed receivables and prepaid expenses and other current assets, the proceeds from the issuance of common stock and the increase in deferred
revenues.

As of June 30, 2002, the Companys principal commitments consisted of obligations under operating leases.

We believe that our current cash balances and the cash flows generated by operations will be sufficient to meet our anticipated cash needs for working capital and capital expenditures for the next 12 months. Thereafter, if cash generated
from operations is insufficient to satisfy our liquidity requirements, we may seek to sell additional equity or convertible debt securities or obtain credit facilities. The decision to sell additional equity or debt securities could be made at any
time and would likely result in

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additional dilution to our stockholders. A portion of our cash may be used
to acquire or invest in complementary businesses or products or to obtain the right to use complementary technologies. From time to time, in the ordinary course of business, we evaluate potential acquisitions of such businesses, products or
technologies. In the fourth quarter of fiscal 2002, we will pay consideration of approximately $67.1 million for the entire issued share capital of RiverSoft plc  see Subsequent Events in Notes to Condensed Consolidated Financial
Statements. However, as part of the assets assumed in the acquisition, the Company expects to receive approximately $64 million in cash.

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RISK FACTORS

The following factors, in addition to the other information contained in this report, should be considered carefully in evaluating the Company and our prospects. This report (including without limitation the following
Risk Factors) contains forward-looking statements (within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934) regarding the Company and our business, financial condition, results of
operations and prospects. Words such as expects, anticipates, intends, plans, believes, seeks, estimates and similar expressions or variations of such words are
intended to identify forward-looking statements, but are not the exclusive means of identifying forward-looking statements in this report. Additionally, statements concerning future matters such as the development of new products, enhancements or
technologies, possible changes in legislation and other statements regarding matters that are not historical are forward-looking statements.

Although forward-looking statements in this
report reflect the good faith judgment of our management, such statements can only be based on facts and factors we currently know about. Consequently, forward-looking statements are inherently subject to risks and uncertainties, and actual results
and outcomes may differ materially from the results and outcomes discussed in the forward-looking statements. Factors that could cause or contribute to such differences in results and outcomes include, but are not limited to, those discussed below
and in Managements Discussion and Analysis of Financial Condition and Results of Operations as well as those discussed elsewhere in this report. Readers are urged not to place undue reliance on these forward-looking statements,
which speak only as of the date of this report. We undertake no obligation to revise or update any forward-looking statements in order to reflect any event or circumstance that may arise after the date of the report.

Our operating results may vary as a result of the current economic slowdown

We face uncertainty in the degree to which the current
economic slowdown will negatively affect growth and capital spending by our existing and potential customers. We have recently experienced increased instances of customers delaying or deferring licenses of our software and maintenance agreement, and
longer lead times needed to close our customer sales. Also we have recently experienced a partial termination of an order from an existing telco customer, that will negatively impact revenue in the quarter ended September 30, 2002 - See
Subsequent Events in Notes to Condensed Consolidated Financial Statements. If the economic conditions in the United States and globally do not improve, or if we experience a worsening in the global economic slowdown, we may continue to
experience material adverse impacts on our business, operating results, and financial condition. We may not be able to accurately anticipate the magnitude of these impacts on future quarterly results.

Because we have a limited operating history in a dynamic market, it is difficult to predict our future operating results.

Because we
operate in a rapidly evolving and dynamic market, it is difficult to predict our future operating results. Although, we first shipped our Netcool/OMNIbus product in January of 1995, our limited operating history and rapidly changing product
development, installation, maintenance and market dynamics make the prediction of future results of operations difficult. Our prospects must be considered in light of the risks, costs and difficulties frequently encountered by companies,
particularly companies in the competitive software industry. We intend to increase our operating expenses to develop new distribution channels, increase our sales and marketing efforts, implement and improve operational, financial and management
information systems, broaden technical services and customer

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support capabilities, fund higher levels of research and development and
expand administrative resources in anticipation of future growth. Our operating results will be harmed if these increased expenditures do not result in increased revenues and profitability.

Our operating results may vary from quarter to quarter, causing our stock price to fluctuate.

Our quarterly revenues and operating results in geographic segments
that we track fluctuate and are difficult to predict. It is possible that in some quarter or quarters our operating results will be below the expectations of public market analysts or investors. In such event, or in the event adverse conditions
prevail, or are perceived to prevail, with respect to our business or financial markets generally, the market price of our common stock may decline significantly.

We realize a
significant portion of our license revenues in the last month of a quarter, frequently in the last weeks or even days of a quarter. As a result, license revenues in any quarter are difficult to forecast because it is substantially dependent on
orders booked and shipped in that quarter. Moreover, our sales cycle, from initial evaluation to delivery of software, varies substantially from customer to customer. Further, we base our expense levels in part on forecasts of future orders and
sales, which are extremely difficult to predict. A substantial portion of our operating expenses is related to personnel, facilities, and sales and marketing programs. The level of spending for such expenses cannot be adjusted quickly and is,
therefore, relatively fixed in the short term. Accordingly, our operating results will be harmed if revenues fall below our expectations in a particular quarter. In addition, the number and timing of large individual sales has been difficult for us
to predict, and large individual sales have, in some cases, occurred in quarters subsequent to those we anticipated, or have not occurred at all. The loss or deferral of one or more significant sales in a quarter could harm our operating
results.

Because of these fluctuations we believe that quarter-to-quarter comparisons of our operating results are not necessarily meaningful or indicative of our future performance. A
number of other factors are likely to cause these variations, including:

| | changes in the demand for our software products and services and the level of product and price competition that we encounter;                                               
|- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| 
| | the timing of new hires and our ability to attract, retain and motivate qualified personnel, including changes in our sales incentives;                                      
| 
| | the mix of products and services sold, including the mix of sales to new and existing customers and through third-party distributors and our direct sales force;             
| 
| | changes in the mix of, and lack of demand from, distribution channels through which our products are sold;                                                                   
| 
| | the length of our sales cycles and the success of our new customer generation activities;                                                                                    
| 
| | spending patterns and budgetary resources of our customers on network management software solutions;                                                                         
| 
| | product life-cycles and the timing of introductions or enhancements of products, or delays in the introductions or enhancements of our products and those of our
competitors;
| 
| | market acceptance of new products;                                                                                                                                           

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| | changes in the renewal rate of maintenance agreements;                                                                                                                                                                                           
|- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| 
| | expansion of international operations, including gains and losses on the conversion to United States dollars of accounts receivable and accounts payable arising from international
operations and the mix of international and domestic revenue;
| 
| | the extent of market consolidation; and                                                                                                                                                                                                          
| 
| | software defects and other product quality problems.                                                                                                                                                                                             

Failure to manage our growth may
adversely affect our business.

Over the past few years, we have added customers, personnel and expanded the scope and geographic area of our operations that has placed and will
continue to place a significant strain upon our management and our operating and financial systems and resources. As of June 30, 2002, we had 664 employees. However, given the uncertainties discussed in this Risk Factors section, failure to align
employee skills and populations with revenue and market requirements would have a material adverse impact on our business and its operating results. In July 2002, the Company announced continued plans to further reduce the workforce.

We need to continue to expand and improve the productivity of our sales force and our technical services and customer support organization.

Our success has always depended in large part on our ability to attract and retain highly skilled sales and technical personnel. In spite of the economic slowdown, competition for these personnel is intense. Sales
personnel are in high demand and are difficult to attract and retain and require nine months, or longer, to become fully productive. Further, because of the expansion of the installed base of our products, the demands on our technical services and
customer support resources have grown rapidly. The loss of services of any of our key personnel, the inability to retain and attract qualified personnel in the future, or delays in hiring required personnel, particularly sales and technical
personnel, could make it difficult to meet key objectives, such as timely product introductions.

We need to continue to expand our distribution channels and retain our existing
third-party distributors.

We need to continue to develop and retain relationships with leading network equipment and telecommunications providers and to expand our third-party
channels of distribution through OEMs, resellers and systems integrators. We are currently investing, and plan to continue to invest, significant resources to develop these relationships and channels of distribution, which could reduce our ability
to generate profits. Third-party distributors accounted for approximately 49%, 42% and 34% of our total revenues in the nine months ended June 30, 2002, fiscal 2001 and 2000, respectively. Our business will be harmed if we are not able to retain
existing distributors or attract additional distributors that market our products effectively. Further, many of our agreements with third-party distributors are nonexclusive, and many of the companies with which we have agreements also have similar
agreements with our competitors or potential competitors. Our third-party distributors have significantly greater sales and marketing resources than we do, and their sales and marketing efforts may conflict with our direct sales efforts. In
addition, although sales through third-party distributors result in reduced sales and marketing expense with respect to such sales, we sell our products to third-party distributors at reduced prices, resulting in lower gross margins on such
third-party sales. We believe that our success

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in penetrating markets for our fault and service level management
applications depends substantially on our ability to maintain our current distribution relationships, in particular, those with Cisco Systems, IBM, Ericsson, Unisphere (Siemens), Sun Microsystems and others. Our business will be harmed if network
equipment and telecommunications providers and distributors discontinue their relationships with us, compete directly with us or form additional competing arrangements with our competitors.

We are dependent on the market for software designed for use with advanced communications services, and the size of this market is unproven.

The market for our
products is in an early stage of development or is developed but not highly penetrated. Although the rapid expansion and increasing complexity of computer networks in recent years and the resulting emergence of service level agreements has increased
the demand for fault and service level management software products, the awareness of and the need for such products is a recent development. Therefore, it is difficult to assess the size of this market, the appropriate features and prices for
products to address this market, the optimal distribution strategy and the competitive environment that will develop.

We are substantially dependent upon telecommunications
carriers and other service providers continuing to purchase our products.

Telecommunications carriers, including Internet service providers, that deliver advanced
communications services to their customers have accounted for approximately 77%, 79% and 82% of our total revenues in the nine months ended June 30, 2002, fiscal 2001 and 2000, respectively. In addition, these providers are an important focus of our
sales strategy. If these customers cease to deploy advanced communications services for any reason, the market for our products will be harmed. Also, delays in the introduction of advanced services, such as network management outsourcing, or the
failure of such services to gain widespread market acceptance or the decision of telecommunications carriers and other service providers not to use our products in the deployment of these services would harm our business.

Consolidations in, or a slowdown in the growth of, the telecommunications industry could harm our business.

We have
derived a substantial amount of our revenues from sales of products and related services to the telecommunications industry. The telecommunications industry has experienced significant growth and consolidation in the past few years, although recent
trends indicate that this growth and capital spending by this industry has decreased and may continue to decrease in the future as a result of a general decline in economic growth in local and international markets. Our business is highly dependent
on the growth of the telecommunications industry and on continued capital spending by our customers in that industry. In the event of further significant slowdown in the growth or capital spending of the telecommunications industry, our business
would be adversely affected. Furthermore, as a result of industry consolidation, there may be fewer potential customers requiring our software in the future. Larger, consolidated telecommunications companies may also use their purchasing power to
create pressure on the prices and the margins we could realize. We cannot be certain that consolidations in, or a slowdown in the growth of, the telecommunication industry will not harm our business.

Our business depends on the continued growth of the Internet.

A significant portion of our revenues comes from telecommunications
carriers, Internet service providers and other customers that rely upon or are driven by the Internet. As a result, our future results

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of operations substantially depend on the continued acceptance and use of
the Internet as a medium for commerce and communication. Our business could be harmed if this growth does not continue or if the rate of technological innovation, deployment or use of the Internet slows or declines. Recent data and reports indicate
that both the growth of significant portions of the Internet and technological innovations have slowed. If these trends continue, they will have an adverse impact on our business.

Furthermore, the growth and development of the market for Internet-based services may prompt the introduction of new laws and regulations. Laws, which impose additional burdens on those companies that conduct business online, could decrease
the expansion of the use of the Internet. A decline in the growth of the Internet could decrease demand for our products and services and increase our cost of doing business, or otherwise harm our business, which could result in a material adverse
effect on the market price of our common stock.

We face intense competition, including from larger competitors with greater resources than our own, which could result in our
losing market share or experiencing a decline in gross margins.

We face intense competition in our markets. As we enter new markets, we encounter additional, market-specific
competitors. In addition, because the software market has relatively low barriers to entry, we are aware of new and potential entrants in portions of our market space. Increased competition is likely to result in price reductions and may result in
reduced gross margins and loss of market share.

Further, many of our competitors have longer operating histories and have significantly greater financial, technical, sales, marketing
and other resources, as well as greater name recognition and a larger customer base, than we do. As a result, they may be able to devote greater resources to the development, promotion, sale and support of their products or to respond more quickly
to new or emerging technologies and changes in customer requirements than we can. Existing competitors could also increase their market share by bundling products having functionality offered by our products with their current applications.
Moreover, our current and potential competitors may increase their share of the fault and service level management market by strategic alliances and/or the acquisition of competing companies. In addition, network operating system vendors could
introduce new or upgrade and extend existing operating systems or environments that include functionality offered by our products, which could render our products obsolete and unmarketable.



Our current and prospective competitors offer a variety of solutions to address the fault and service level and enterprise network management markets and generally fall
within the following five categories:

| | customers internal design and development organizations that produce service level management and network management applications for their particular needs, in some cases using multiple
instances of products from hardware and software vendors such as Compaq, Hewlett-Packard Company and Cabletron Systems, Inc.;
|- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| 
| | vendors of network and systems management frameworks including Computer Associates International, Inc.;                                                                                                                                                                                                                  
| 
| | vendors of network and systems management applications including Hewlett-Packard Company and BMC Software, Inc;                                                                                                                                                                                                          
| 
| | providers of specific market applications; and                                                                                                                                                                                                                                                                           

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| | systems integrators serving the telecommunications industry which primarily provide programming services to develop customer specific applications including TCSI Corporation, TTI and Agilent Technologies,
Inc.
|- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Many of our existing and potential customers and distributors continuously evaluate whether to design and develop their own network operations support and
management applications or purchase them from outside vendors. Sometimes these customers internally design and develop their own software solutions for their particular needs and therefore may be reluctant to purchase products offered by independent
vendors such as ours. As a result, we must continuously educate existing and prospective customers as to the advantages of our products versus internally developed network operations support and management applications.

If we ship products that contain defects, the market acceptance of our products and our reputation will be harmed, and our customers could seek to recover their damages from
us.

Complex software products frequently contain errors or defects, especially when first introduced or when new versions or enhancements are released. Despite our extensive
product testing, we have in the past released versions of Netcool/OMNIbus with defects and have discovered software errors in certain of our products after their introduction. For example, version 3.0 of Netcool/OMNIbus, released in 1996, had a
number of material defects. Version 1.0 of Netcool/Reporter, released in 1998, had features and performance characteristics that limited market acceptance. A significant portion of our technical personnel resources were required to address these
defects. Because of these defects, we could continue to experience delays in or failure of market acceptance of products, or damage to our reputation or relationships with our customers. Any defects and errors in new versions or enhancements of our
products after commencement of commercial shipments would harm our business.

In addition, because our products are used to monitor and address network problems and avoid failures of
the network to support critical business functions, any design defects, software errors, misuse of our products, incorrect data from network elements or other potential problems within or out of our control that may arise from the use of our
products could result in financial or other damages to our customers. Our customers could seek to have us pay for these losses. Although we maintain product liability insurance, it may not be adequate. Further, although our license agreements with
our customers typically contain provisions designed to limit our exposure to potential claims as well as any liabilities arising from such claims, such provisions may not effectively protect us against such claims and the liability and costs
associated therewith.

The sales cycle for our software products is long, and the delay or failure to complete one or more large license transactions in a quarter could cause our
operating results to fall below our expectations.

The sales cycle is highly customer specific and can vary from a few weeks to many months. The software requirements of
customers is highly dependent on many factors, including but not limited to their projections of business growth, capital budgets and anticipated cost savings from implementation of our software. Our delay or failure to complete one or more large
license transactions in a quarter could harm our operating results. Our software is generally used for division-wide or enterprise-wide, business-critical purposes and involves significant capital commitments by customers. Potential customers
generally commit significant resources to an evaluation of available enterprise software and requires us to expend substantial time, effort and money educating them about the value of our solutions. Licensing of our software products often requires
an extensive sales effort throughout a

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customers organization because decisions to license such software
generally involve the evaluation of the software by a significant number of customer personnel in various functional and geographic areas, each often having specific and conflicting requirements. A variety of factors, including actions by
competitors and other factors over which we have little or no control, may cause potential customers to favor a particular supplier or to delay or forego a purchase.

We depend on
our key personnel, and the loss of any of our key personnel could harm our business.

Our success is substantially dependent upon a limited number of key management, sales,
product development, technical services and customer support personnel. The loss of the services of one or more of such key employees could harm our business. We do not generally have employment contracts with key personnel. In addition, we are
dependent upon our continuing ability to attract, train and retain additional highly qualified management, sales, product development, technical services and customer support personnel. We have at times experienced and continue to experience
difficulty in recruiting qualified personnel. Also, the volatility or lack of positive performance in our stock price may also adversely affect our ability to attract and retain key employees, who often expect to realize value from stock options.
Because we face intense competition in our recruiting activities, we may be unable to attract and/or retain qualified personnel.

We have acquired other businesses and we may make
additional acquisitions in the future, which will complicate our management tasks and could result in substantial expenditures.

We have acquired other businesses and we may
make additional acquisitions in the future, which will complicate our management tasks and could result in substantial expenditures. For example, on December 28, 1999 we completed the acquisition of Calvin Alexander Networking, Inc., a developer of
network auto-discovery software. On July 18, 2000, the Company completed the acquisition of NetOps Corporation, a developer of network diagnostic software. In June 2002, Micromuse commenced a cash offer for RiverSoft plc. - See Subsequent
Events in Notes to Condensed Financial Statements. Because of these acquisitions, we are integrating distinct products, customers and corporate cultures into our own. These past and potential future acquisitions create numerous risks for us,
including:

| | failure to successfully assimilate acquired operations and products;                                                          
|- | ------------------------------------------------------------------------------------------------------------------------------
| 
| | diversion of our managements attention from other matters;                                                                   
| 
| | loss of key employees of acquired companies;                                                                                  
| 
| | substantial transaction costs;                                                                                                
| 
| | substantial liabilities or exposures in the acquired entity that were not known or accurately evaluated or forecast by us; and
| 
| | substantial additional costs charged to operations as a result of the failure to consummate a potential acquisition.          

Further,
some of the products we acquire would require significant additional development before they can be marketed and may not generate revenue at levels we anticipate. Moreover, our future acquisitions, if any, may result in issuances of our equity
securities which dilute our stockholders, the incurrence of debt and large one-time write-offs. It is possible that our efforts to consummate or integrate acquisitions will not be successful, which would harm our business.

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We have relied and expect to continue to rely on a limited
number of products for a significant portion of our revenues.

All of our revenues have been derived from licenses for our Netcool family of products and related maintenance,
training and consulting services. We currently expect that Netcool/OMNIbus-related revenues will continue to account for a substantial percentage of our revenues beyond fiscal 2001 and for the foreseeable future thereafter. Although we have
Netcool/OMNIbus for Voice Networks, Netcool/Precision, Netcool/Visionary and other products, our future operating results, particularly in the near term, are significantly dependent upon the continued market acceptance of Netcool/OMNIbus,
improvements to Netcool/OMNIbus and new and enhanced Netcool/OMNIbus applications. Our business will be harmed if Netcool/OMNIbus does not continue to achieve market acceptance or if we fail to develop and market improvements to Netcool/OMNIbus or
new or enhanced products. The life cycles of Netcool/OMNIbus, including the Netcool/OMNIbus applications, are difficult to estimate due in large part to the recent emergence of many of our markets, the effect of future product enhancements and
competition. A decline in the demand for Netcool/OMNIbus as a result of competition, technological change or other factors would harm our business.

We have relied and expect to
continue to rely on a limited number of customers for a significant portion of our revenues.

We derive a significant portion of our revenues in any particular period from a
limited number of customers. See Concentration of Revenues in Notes to Condensed Consolidated Financial Statements. We expect to derive a significant portion of our revenues from a limited number of customers in the future. If a significant
customer, or group of customers, cancels or delays orders for our products, or does not continue to purchase our products at or above historical levels, our business will be harmed. For example, pre-existing customers may be part of, or become part
of, large organizations that standardize using a competitive product. The terms of our agreements with our customers typically contain a one-time license fee and a prepayment of one year of maintenance fees. The maintenance agreement is renewable
annually at the option of the customer and there are no minimum payment obligations or obligations to license additional software. Therefore, we generally do not have long-term customer contracts upon which we can rely for future
revenues.

Our international sales and operations expose us to currency fluctuation risks and other inherent risks.

We license our products in foreign countries. In addition, we maintain a significant portion of our operations, including the bulk of our software development operations, in the United Kingdom. Fluctuations in the
value of these currencies relative to the United States dollar have adversely impacted our results in the past and may do so in the future. See Geographic and Segment Information in Notes to Condensed Consolidated Financial Statements for
information concerning revenues outside the United States. We expect that international license, maintenance and consulting revenues will continue to account for a significant portion of our total revenues in the future. We pay the expenses of our
international operations in local currencies and do not currently engage in hedging transactions with respect to such obligations.

Our international operations and revenues involve a
number of other inherent risks, including:

| | longer receivables collection periods and greater difficulty in accounts receivable collection;
|- | -----------------------------------------------------------------------------------------------

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| | difficulty in staffing and generally higher costs associated with managing foreign operations;                                                                                                                                                                                                                                                                   
|- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| 
| | an even lengthier sales cycle than with domestic customers;                                                                                                                                                                                                                                                                                                      
| 
| | the impact of possible recessionary environments in economies outside the United States;                                                                                                                                                                                                                                                                         
| 
| | sales in Europe and certain other parts of the world generally are adversely affected in the quarter ending September 30, as many customers reduce their business activities during
the summer months. If our international sales become a greater component of total revenue, these seasonal factors may have a more pronounced effect on our operating results;
| 
| | changes in regulatory requirements, including a slowdown in the rate of privatization of telecommunications service providers, reduced protection for intellectual property rights in
some countries and tariffs and other trade barriers;                                                                                                                       
| 
| | changes in or failure to be aware of or to account for payroll, stock option, employee stock purchase and business related taxation;                                                                                                                                                                                                                             
| 
| | political, economic or terrorism induced instability;                                                                                                                                                                                                                                                                                                            
| 
| | lack of acceptance of non-localized products;                                                                                                                                                                                                                                                                                                                    
| 
| | legal and cultural differences in the conduct of business; and                                                                                                                                                                                                                                                                                                   
| 
| | immigration regulations that limit our ability to deploy our employees.                                                                                                                                                                                                                                                                                          

We intend to enter into
additional international markets and to continue to expand our operations outside of the United States by expanding our direct sales force and pursuing additional strategic relationships. Such expansion will require significant management attention
and expenditure of significant financial resources and could adversely affect our ability to generate profits. If we are unable to establish additional foreign operations in a timely manner, our growth in international sales will be limited, and our
business could be harmed.

Rapid technological change, including evolving industry standards and regulations and new product introductions by our competitors, could render our
products obsolete.

Rapid technological change, including evolving industry standards and regulations and new product introductions by our competitors, could render our products
obsolete. As a result, the life cycles of our products are difficult to estimate and we must constantly develop, market and sell new and enhanced products. If we fail to do so, our business will be harmed. For example, the widespread adoption of new
architecture standards for managing telecommunications networks (for example TMN architecture) would force us to adapt our products to such standard, which we may be unable to do on a timely basis or at all. In addition, to the extent that any
product upgrade or enhancement requires extensive installation and configuration, current customers may postpone or forgo the purchase of new versions of our products. Further, the introduction or announcement of new product offerings by us or one
or more of our competitors may cause our customers to defer licensing of our existing products.

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Our products operate on third-party software platforms, and we could
lose market share if our products do not operate on the hardware and software operating platforms employed by our customers.

Our products operate on third-party software
platforms and we could lose market share if our products do not operate on the hardware and software operating platforms employed by our customers. Our products are designed to operate on a variety of hardware and software platforms employed by our
customers in their networks. We must continually modify and enhance our products to keep pace with changes in hardware and software platforms and database technology. As a result, uncertainties related to the timing and nature of new product
announcements, introductions or modifications by systems vendors, particularly Sun Microsystems, Inc., International Business Machines Corporation, Hewlett-Packard Company, Cabletron Systems, Inc. and Cisco Systems, Inc. and by vendors of relational
database software, particularly Oracle Corporation and Sybase, Inc., could harm our business.

Our efforts to protect our intellectual property may not be adequate, or a
third-party could claim that we are infringing its proprietary rights.

We cannot guarantee that the steps we have taken to protect our proprietary rights will be adequate to
deter misappropriation of our intellectual property. In addition, we may not be able to detect unauthorized use of our intellectual property and take appropriate steps to enforce our rights. If third parties infringe or misappropriate our trade
secrets, copyrights, patents, trademarks or other proprietary information or intellectual property, our business could be harmed. In addition, protection of intellectual property in many foreign countries is weaker and less reliable than in the
United States, so as our international operations expand, the risk that we will fail to adequately protect our intellectual property increases. Further, while we believe that our products and trademarks do not infringe upon the proprietary rights of
third parties, other parties may assert that our products infringe, or may infringe, their proprietary rights or we have not fulfilled the terms of agreements with them. Any such claims, with or without merit could be time-consuming, result in
costly litigation and diversion of technical and management personnel, cause product shipment delays or require us to develop non-infringing technology or enter into royalty, licensing or other agreements. Such royalty or licensing agreements, if
required, may not be available on terms acceptable to us or at all. We expect that software product developers will be increasingly subject to infringement claims as the number of products and competitors in our industry segment grows and the
functionality of products in different industry segments overlaps.

We rely on software that we have licensed from third-party developers to perform key functions in our
products.

We rely on software that we license from third parties, including software that is integrated with internally developed software and used in our products to perform
key functions. We could lose the right to use this software or it could be made available to us only on commercially unreasonable terms. Although we believe that alternative software is available from other third-party suppliers or internal
developments, the loss of or inability to maintain any of these software licenses or the inability of the third parties to enhance in a timely and cost-effective manner their products in response to changing customer needs, industry standards or
technological developments could result in delays or reductions in product shipments by us until equivalent software could be developed internally or identified, licensed and integrated, which would harm our business.

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Our stock price is volatile.

The market price of our common stock has been and is likely to continue to be highly volatile. The market price may vary in response to many factors, some of which are outside our control,
including:

| | actual or anticipated fluctuations in our operating results;                                       
|- | ---------------------------------------------------------------------------------------------------
| 
| | announcements of technological innovations, new products or new contracts by us or our competitors;
| 
| | developments with respect to intellectual property rights;                                         
| 
| | adoption of new accounting standards affecting the software industry; and                          
| 
| | general market conditions and other factors.                                                       

In addition, the stock market has from time to
time experienced significant price and volume fluctuations that have particularly affected the market price for the common stock of technology companies. These types of broad market fluctuations may adversely affect the market price of our common
stock. In the past, following periods of volatility in the market price of a companys securities, securities class action litigation has often been initiated against such company. Such litigation could result in substantial costs and a
diversion of our managements attention and resources that could harm our business.

General economic and market conditions may impair our business.

Segments of the software industry have experienced significant economic downturns characterized by decreased product demand, price erosion, work slowdowns and layoffs. Our operations has experienced
substantial fluctuations as a consequence of general economic conditions affecting the timing of orders from major customers and other factors affecting capital spending. Although we have a diverse client base, we target certain market segments.
Therefore, any economic downturns in general or in the targeted segments in particular would harm our business.

Our goodwill and other intangible assets may become
impaired.

Due to rapidly changing market conditions, our goodwill and other intangible assets may become impaired such that their carrying amounts may not be recoverable, and
we may be required to record an impairment charge impacting our financial position. As of June 30, 2002, we had approximately $27.8 million of goodwill and other intangible assets, which were primarily related to the acquisitions of CAN in December
1999 and NetOps in July 2000. The Company regularly performs reviews to determine if the carrying value of assets is impaired. The purpose for the review is to identify any facts or circumstances, either internal or external, which indicate that the
carrying value of the asset cannot be recovered. No such impairment has been indicated to date. However, if for example the demand for the products and services underlying this goodwill decreases as a result of the general economic slowdown or other
causes and, as a result, the estimated future undiscounted net cash flows from the acquired businesses are insufficient to recover the carrying value of the assets over their estimated lives, we will record an impairment of our goodwill and
recognize asset impairment charges in the quarter in which that impairment is determined. Asset impairment charges of this nature could be large and could have a material adverse effect on our financial condition and reported results of
operations.

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Future sales of our common stock may affect the market price of our
common stock.

As of June 30, 2002, we had approximately 74.7 million shares of common stock outstanding, excluding approximately 12.6 million shares subject to options
outstanding as of such date under our stock option plans that are exercisable at prices ranging from approximately $0.58 to $106.22 per share. We cannot predict the effect, if any, that future sales of common stock or the availability of shares of
common stock for future sale, will have on the market price of common stock prevailing from time to time. Sales of substantial amounts of common stock (including shares issued upon the exercise of stock options), or the perception such sales could
occur, may materially and adversely affect prevailing market prices for common stock. In addition, tax charges resulting from the exercise of stock options could adversely affect the reported results of operations.

We have various mechanisms in place to discourage takeover attempts.

Certain provisions of our certificate of incorporation and bylaws and
certain provisions of Delaware law could delay or make difficult a change in control of Micromuse that a stockholder may consider favorable. The provisions include:

| | blank check: preferred stock that could be used by our board of directors to increase the number of outstanding shares and thwart a takeover attempt; and
|- | -----------------------------------------------------------------------------------------------------------------------------------------------------------
| 
| | a classified board of directors with staggered, two-year, terms, which may lengthen the time required to gain control of the board of directors            

In addition, Section 203 of the General Corporation Law of the State of Delaware, which is applicable to us, and our stock incentive plans, may discourage, delay or prevent a change of control of
Micromuse.

The recent terrorist attacks are unprecedented events that have created many economic and political uncertainties, some of which may harm our business and prospects
and our ability in general to conduct business in the ordinary course.

Terrorist attacks in New York and Washington, D.C. in September 2001 have disrupted commerce throughout
the world. The continued threat of terrorism and the resulting military, economic and political response and heightened security measures may cause significant disruption to commerce throughout the world. To the extent that this disruption results
in a general decrease in our customers spending, our business and results of operations could be materially and adversely affected. We are unable to predict whether the threat of terrorism or the responses thereto will result in any long-term
commercial disruptions or if such activities or responses will have a long-term adverse effect on our business, results of operations or financial condition. These and other developments arising out of the attacks may make the occurrence of one or
more of the factors discussed under Risk Factors more likely to occur.

Year 2000 issues could impair our business.

We have designed and tested our products to be Year 2000 compliant. We continue to believe that our products performed well during the roll-over from 1999 to 2000 and February 29, 2000. However, any undetected or
unreported errors or defects associated with Year 2000 date functions could result in material costs to us. In addition, certain components of our products process timestamp information from third-party applications or local operating systems. If
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operating systems are not Year 2000 compliant, our products that
process such timestamp information may not be Year 2000 compliant.

In our standard license agreements, we provide certain warranties to licensees that our software routines and
programs are Year 2000 compliant. If any of our licensees experience Year 2000 problems, such licensees could assert claims for damages against us. Any such claims or litigation could result in substantial costs and diversion of our resources even
if ultimately decided in our favor. Based on work done to date and our best estimates, we have not incurred material costs and do not expect to incur future material costs in addressing the Year 2000 issue in our systems and products.

Euro conversion may adversely affect our business.

On January 1, 2002, various European countries replaced their
national currencies with a new single currency known as the Euro. Issues we are reviewing as a result of the Euro include updating information technology systems, assessing currency risk, reviewing licensing agreements and contracts for currency
issues, and processing tax and accounting records. Although we have experienced no adverse effect on our financial conditions or results of operations since its introduction and do not currently expect a material adverse effect, we cannot assure
that issues relating to the Euro will not harm our business.

Power blackouts and rising energy costs in California could disrupt our business and increase our
expenses.

Our principal executive offices are located in San Francisco, California. Our principal product development operations are located in London, and we have other
offices in more than 10 cities outside California. In fiscal 2001, California experienced rolling blackouts of electricity and rising energy costs throughout the state. We have not experienced any material power disruptions or material energy
expense increases to date. However, a continuation or worsening of these adverse energy circumstances may disrupt our ability to market our products or provide services to customers or otherwise adversely affect our business.

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Item 3. Quantitative and Qualitative Disclosures about Market Risk

Foreign Currency Hedging Instruments

We transact business in various foreign currencies. Accordingly, we are subject to exposure from adverse movements in foreign currency exchange rates. This exposure is primarily related to local currency denominated
revenues and operating expenses in the U.K. However, as of June 30, 2002, no hedging contracts were outstanding.

We currently do not use financial instruments to hedge local currency
denominated operating expenses in the U.K. Instead, we believe that a natural hedge exists, in that local currency revenues will substantially offset the local currency denominated operating expenses. We assess the need to utilize financial
instruments to hedge currency exposures on an ongoing basis.

We do not use derivative financial instruments for speculative trading purposes, nor do we hedge our foreign currency
exposure in a manner that entirely offsets the effects of changes in foreign exchange rates. We regularly review our hedging program and may as part of this review determine at any time to change our hedging program.

Fixed Income Investments

Our exposure to market risks for changes in interest rates relate primarily to investments in debt securities
issued by U.S. government agencies and corporate debt securities. We place our investments with high credit quality issuers and, by policy, limits the amount of the credit exposure to any one issuer.

Our general policy is to limit the risk of principal loss and ensure the safety of invested funds by limiting market and credit risk. All highly liquid investments with less than three months to maturity are
considered to be cash equivalents; investments with maturities between three and twelve months are considered to be short-term investments; investments with maturities in excess of twelve months are considered to be long-term investments. The
weighted average pre-tax interest rate on the investment portfolio is approximately 3.3%.

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Part II  OTHER INFORMATION

Item 1. Legal Proceedings.

The Company is routinely involved in legal and administrative proceedings in the ordinary course of its business.
Management does not regard any of those proceedings to be material.

Item 2.        Changes in Securities and Use of Proceeds.

Not applicable.

Item 3.        Defaults upon Senior Securities.

Not applicable.

Item 4.        Submission of Matters to a Vote of Security Holders.

The voting results and related information from our
annual meeting held on January 31, 2002, were reported in Item 4 of our Quarterly Report on Form 10-Q filed with the SEC on February 13, 2002, which item is incorporated herein by this reference.

Item 5.        Other Information.

Not applicable.

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Item 6. Exhibits and Reports on Form 8-K:

(a)  Exhibits

|Exhibit Number |  | Description                                                                                                                                                                                         
|-------------- |  | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|               |  |                                                                                                                                                                                                     
|3.1            |  | Restated Certificate of Incorporation of the Registrant (incorporated by reference from exhibit 3.1 in our Form 10-K filed with the SEC on December 21, 2001).                                      
|               |  |                                                                                                                                                                                                     
|3.2            |  | Amended and Restated Bylaws of the Registrant (incorporated by reference from exhibit 3.2 in our amended registration statement on Form S-1, No. 333-58975, as filed with the SEC on
July 13, 1998).
|               |  |                                                                                                                                                                                                     
|99.1           |  | Certifications of the Chief Executive Officer and the Chief Financial Officer of Registrant required by Section 906 of the Sarbanes-Oxley Act of 2002                                               
|              
|              

(b)  Reports on Form 8-K

A
current report on Form 8-K was filed with the Securities and Exchange Commission by Micromuse on June 19, 2002 and June 25, 2002, to report the commencement of a cash tender to acquire all of the issued shared capital of RiverSoft plc.

A current report on Form 8-K was filed with the Securities and Exchange Commission by Micromuse on July 24, 2002, to report valid acceptance of the offer by RiverSoft plc shareholders representing
approximately 90.8% of total issued share capital.

A current report on Form 8-K was filed with the Securities and Exchange Commission by Micromuse on July 30, 2002, giving formal
notices under Section 429 of the Companies Act 1985 (UK) to acquire compulsorily all those RiverSoft plc shares in respect of which valid acceptances have not been received.

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SIGNATURES

Pursuant to the requirements 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, on August 13, 2002.

| |                                                                               
| | ------------------------------------------------------------------------------
| | MICROMUSE INC.(Registrant)                                                    
| |                                                                               
| |                                                                               
| | By: /s/ GREGORY Q. BROWN                                                      
| | Gregory Q. Brown                                                              
| | Chairman and Chief Executive Officer(Duly Authorized Officer)                 
| |                                                                               
| |                                                                               
| |                                                                               
| | By: /s/ MICHAEL L. LUETKEMEYER                                                
| | Michael L. Luetkemeyer                                                        
| | Senior Vice President and Chief Financial Officer(Principal Financial Officer)
| |                                                                               

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