------------------------------
                                                          OMB APPROVAL
                                                  ------------------------------
                                                  OMB Number:          3235-0060
                                                  Expires:          May 31, 2000
                                                  Estimated average burden
                                                  hours per response .....  5.00
                                                  ------------------------------

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

                                    FORM 8-K

                                 CURRENT REPORT
     Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934

DATE OF REPORT (DATE OF EARLIEST EVENT REPORTED)    July 18, 2000
                                                --------------------------------

                                 MICROMUSE INC.
--------------------------------------------------------------------------------
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

          Delaware                   000-23783                   94-3288385
--------------------------------------------------------------------------------
(State or other jurisdiction        (Commission                (IRS Employer
    of incorporation)               File Number)             Identification No.)

139 Townsend Street, San Francisco, California                       94107
--------------------------------------------------------------------------------
(Address of principal executive offices)                          (Zip Code)

Company's telephone number, including area code         (415) 538-9090
                                               ---------------------------------

--------------------------------------------------------------------------------
          (Former name or former address, if changed since last report)

<PAGE>

ITEM 2. Acquisition or Disposition of Assets.

            On July 18, 2000, Micromuse acquired NetOps Corporation, a Delaware
corporation ("NetOps"), by the statutory merger (the "Merger") of a wholly-owned
subsidiary of Micromuse, Salamander Acquisition Corp., a Delaware corporation
("Merger Sub"), with and into NetOps. The Merger was accomplished pursuant to
the Agreement and Plan of Reorganization, dated as of June 21, 2000, among
Micromuse, NetOps and Merger Sub (the "Merger Agreement"), and a related
Certificate of Merger. As a result of the Merger, Micromuse became the owner of
100% of the issued and outstanding shares of NetOps common stock and preferred
stock and each outstanding share of NetOps common stock was converted into
 .006705 shares of Micromuse's Common Stock, each outstanding share of NetOps
Series A Preferred Stock was converted into .023016 shares of Micromuse's Common
Stock and each outstanding share of NetOps Series B Preferred Stock was
converted into .022930 shares of Micromuse's Common Stock. A total of
approximately 143,000 shares of Micromuse's Stock will be issued to former
NetOps stockholders in exchange for the acquisition by Merger Sub of all
outstanding NetOps capital stock. The terms of the Merger Agreement were the
result of arm's-length negotiations among the parties. The transaction is
intended to qualify as a tax-free reorganization under the Internal Revenue code
of 1986, as amended, and will be accounted for using the purchase method of
accounting.

            The shares issued to NetOps stockholders were issued pursuant to an
exemption from registration under the Securities Act of 1933, as amended. In
connection with the Merger, Micromuse assumed NetOps' outstanding stock options
(other than options cancelled in connection with the Merger), which remain
outstanding as options to purchase shares of Micromuse's Common Stock.

            The acquisition by Micromuse of shares of NetOps common stock
pursuant to the Merger Agreement is deemed an indirect acquisition of the assets
of NetOps represented thereby, including NetOps' plant, equipment and other
physical property. NetOps utilizes such assets as a provider of realtime,
device-centric diagnosis software that explains why a problem occurred in a
company's network infrastructure, at the device level. NetOps' software,
marketed under the "Visionary" name, allows network operations personnel to
receive realtime information on the location of critical network faults and how
they might affect the availability of network-based business services. Micromuse
intends to continue to utilize such assets in the conduct of its business as a
leading provider of fault and service level management software.

            Immediately prior to the Merger, all of the issued and outstanding
shares of capital stock of NetOps were owned by the stockholders of NetOps.
Micromuse is not aware of any pre-existing material relationship between such
stockholders and Micromuse, or between such stockholders and Micromuse's
affiliates, directors or officers, or any associate of any such affiliate,
director or officer.

ITEM 7. Financial Statements, Pro Forma Financial Information and Exhibits.

            (a) Financial Statements of Business Acquired. To be filed by
Amendment to this Current Report on Form 8-K not later than 60 days after the
filing of this Current Report.


                                       2
<PAGE>

            (b) Pro Forma Condensed Combined Financial Statements. To be filed
by Amendment to this Current Report on Form 8-K not later than 60 days after the
filing of this Current Report.

            (c) Exhibits:

Exhibit
Number
------

  2.1       Agreement and Plan of Reorganization, dated as of June 21, 2000, by
            and among Micromuse, Salamander Acquisition Corp. and NetOps
            Corporation.

                                   SIGNATURES

            Pursuant to the requirements of the Securities Act of 1934, as
amended, Micromuse has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.

                                       MICROMUSE INC.


Dated: August 2, 2000                  By: /s/ Stephen Allott
                                           -------------------------------------
                                           Stephen Allott
                                           Chief Financial Officer and President


                                       3
<PAGE>

                                  EXHIBIT INDEX

                             DESCRIPTION OF DOCUMENT

Exhibit
Number
------

  2.1       Agreement and Plan of Reorganization, dated as of June 21, 2000, by
            and among Micromuse, Salamander Acquisition Corp. and NetOps
            Corporation.


                                       4
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{"company-data": {"conformed-name": "MICROMUSE INC", "cik": "0001036425", "assigned-sic": "7372", "irs-number": "943288385", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "000-23783", "film-number": "684623"}, "business-address": {"street1": "139 TOWNSEND ST", "street2": "MEZZANINE FLOOR", "city": "SAN FRANCISCO", "state": "CA", "zip": "94107", "phone": "4155389090"}, "mail-address": {"street1": "139 TOWNSEND STREET", "city": "SAN FRANCISCO", "state": "CA", "zip": "94107"}}
------------------------------
                                                          OMB APPROVAL
                                                  ------------------------------
                                                  OMB Number:          3235-0060
                                                  Expires:          May 31, 2000
                                                  Estimated average burden
                                                  hours per response .....  5.00
                                                  ------------------------------

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

                                    FORM 8-K

                                 CURRENT REPORT
     Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934

DATE OF REPORT (DATE OF EARLIEST EVENT REPORTED)    July 18, 2000
                                                --------------------------------

                                 MICROMUSE INC.
--------------------------------------------------------------------------------
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

          Delaware                   000-23783                   94-3288385
--------------------------------------------------------------------------------
(State or other jurisdiction        (Commission                (IRS Employer
    of incorporation)               File Number)             Identification No.)

139 Townsend Street, San Francisco, California                       94107
--------------------------------------------------------------------------------
(Address of principal executive offices)                          (Zip Code)

Company's telephone number, including area code         (415) 538-9090
                                               ---------------------------------

--------------------------------------------------------------------------------
          (Former name or former address, if changed since last report)
ITEM 2. Acquisition or Disposition of Assets.

            On July 18, 2000, Micromuse acquired NetOps Corporation, a Delaware
corporation ("NetOps"), by the statutory merger (the "Merger") of a wholly-owned
subsidiary of Micromuse, Salamander Acquisition Corp., a Delaware corporation
("Merger Sub"), with and into NetOps. The Merger was accomplished pursuant to
the Agreement and Plan of Reorganization, dated as of June 21, 2000, among
Micromuse, NetOps and Merger Sub (the "Merger Agreement"), and a related
Certificate of Merger. As a result of the Merger, Micromuse became the owner of
100% of the issued and outstanding shares of NetOps common stock and preferred
stock and each outstanding share of NetOps common stock was converted into
 .006705 shares of Micromuse's Common Stock, each outstanding share of NetOps
Series A Preferred Stock was converted into .023016 shares of Micromuse's Common
Stock and each outstanding share of NetOps Series B Preferred Stock was
converted into .022930 shares of Micromuse's Common Stock. A total of
approximately 143,000 shares of Micromuse's Stock will be issued to former
NetOps stockholders in exchange for the acquisition by Merger Sub of all
outstanding NetOps capital stock. The terms of the Merger Agreement were the
result of arm's-length negotiations among the parties. The transaction is
intended to qualify as a tax-free reorganization under the Internal Revenue code
of 1986, as amended, and will be accounted for using the purchase method of
accounting.

            The shares issued to NetOps stockholders were issued pursuant to an
exemption from registration under the Securities Act of 1933, as amended. In
connection with the Merger, Micromuse assumed NetOps' outstanding stock options
(other than options cancelled in connection with the Merger), which remain
outstanding as options to purchase shares of Micromuse's Common Stock.

            The acquisition by Micromuse of shares of NetOps common stock
pursuant to the Merger Agreement is deemed an indirect acquisition of the assets
of NetOps represented thereby, including NetOps' plant, equipment and other
physical property. NetOps utilizes such assets as a provider of realtime,
device-centric diagnosis software that explains why a problem occurred in a
company's network infrastructure, at the device level. NetOps' software,
marketed under the "Visionary" name, allows network operations personnel to
receive realtime information on the location of critical network faults and how
they might affect the availability of network-based business services. Micromuse
intends to continue to utilize such assets in the conduct of its business as a
leading provider of fault and service level management software.

            Immediately prior to the Merger, all of the issued and outstanding
shares of capital stock of NetOps were owned by the stockholders of NetOps.
Micromuse is not aware of any pre-existing material relationship between such
stockholders and Micromuse, or between such stockholders and Micromuse's
affiliates, directors or officers, or any associate of any such affiliate,
director or officer.

ITEM 7. Financial Statements, Pro Forma Financial Information and Exhibits.

            (a) Financial Statements of Business Acquired. To be filed by
Amendment to this Current Report on Form 8-K not later than 60 days after the
filing of this Current Report.

                                       2
(b) Pro Forma Condensed Combined Financial Statements. To be filed
by Amendment to this Current Report on Form 8-K not later than 60 days after the
filing of this Current Report.

            (c) Exhibits:

Exhibit
Number
------

  2.1       Agreement and Plan of Reorganization, dated as of June 21, 2000, by
            and among Micromuse, Salamander Acquisition Corp. and NetOps
            Corporation.

                                   SIGNATURES

            Pursuant to the requirements of the Securities Act of 1934, as
amended, Micromuse has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.

                                       MICROMUSE INC.

Dated: August 2, 2000                  By: /s/ Stephen Allott
                                           -------------------------------------
                                           Stephen Allott
                                           Chief Financial Officer and President

                                       3
EXHIBIT INDEX

                             DESCRIPTION OF DOCUMENT

Exhibit
Number
------

  2.1       Agreement and Plan of Reorganization, dated as of June 21, 2000, by
            and among Micromuse, Salamander Acquisition Corp. and NetOps
            Corporation.

                                       4