As filed with the Securities and Exchange Commission on December 14, 2004

Registration Number 333-____________

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

FORM S-8

REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

FAIR ISAAC CORPORATION

Braun Consulting, Inc. 1998 Employee Long Term Stock Investment Plan
Braun Consulting, Inc. 1998 Executive Long Term Stock Investment Plan
Braun Consulting, Inc. 1999 Independent Director Stock Option Plan
Braun Consulting, Inc. 2002 Employee Long Term Stock Investment Plan, as amended
(Full title of the plan)

Andrea M. Fike, Esq.
Vice President, General Counsel and Secretary
Fair Isaac Corporation
901 Marquette Avenue, Suite 3200
Minneapolis, Minnesota 55402
(612) 758-5260
(Name, address and telephone number of agent for service)

Calculation of Registration Fee

This Registration Statement on Form S-8 is filed by Fair Isaac Corporation (the “Company”) and relates to 87,139 shares of Common Stock, par value $0.01 per share (“Common Stock”) issuable pursuant to the Braun Consulting, Inc. 1998 Employee Long Term Stock Investment Plan, 23,407 shares of Common Stock issuable pursuant to the Braun Consulting, Inc. 1998 Executive Long Term Stock Investment Plan, 8,353 shares of Common Stock issuable pursuant to the Braun Consulting, Inc. 1999 Independent Director Stock Option Plan and 88,303 shares of Common Stock issuable pursuant to the Braun Consulting, Inc. 2002 Employee Long Term Stock Investment Plan, as amended. All of these Plans were assumed by the Company in connection with the Agreement and Plan of Merger among Braun Consulting, Inc., the Company and a wholly-owned subsidiary of the Company, pursuant to which Braun Consulting, Inc. became a wholly-owned subsidiary of the Company on November 10, 2004.

Part I — Information Required in the Section 10(a) Prospectus

     The documents containing the information specified in Part I of Form S-8 have been or will be sent or given to participants as specified by Rule 428(b)(1) under the Securities Act.

Part II — Information Required in the Registration Statement

Item 3. Incorporation of Documents by Reference

     The following documents filed with the Securities and Exchange Commission (the “Commission”) by the Company are incorporated in this Registration Statement by reference:

     All reports and other documents filed by the Company with the Commission pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of this Registration Statement and prior to the filing of a post-effective amendment which indicates that all securities offered have been sold or which deregisters all securities then remaining unsold shall be deemed to be incorporated by reference in and to be a part of this Registration Statement from the date of filing of such documents.

     Any statement contained in a document incorporated by reference herein shall be modified or superseded for purposes of this Registration Statement if and to the extent it is modified or superseded by a statement in this Registration Statement or in a document which is also incorporated by reference in this Registration Statement. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement.

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Item 4. Description of Securities

     Not applicable.

Item 5. Interests of Named Experts and Counsel

     Not applicable.

Item 6. Indemnification of Directors and Officers

     The Company is incorporated under the laws of the State of Delaware. Section 145 of the General Corporation Law of the State of Delaware provides in relevant part as follows:

A corporation shall have the power to indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (other than an action by or in the right of the corporation) by reason of the fact that the person is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, against expenses (including attorneys’ fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by the person in connection with such action, suit or proceeding if the person acted in good faith and in a manner the person reasonably believed to be in or not opposed to the best interest of the corporation and, with respect to any criminal action or proceeding, had no reasonable cause to believe the person’s conduct was unlawful. The termination of any action, suit or proceeding by judgment, order, settlement, conviction or upon a plea of nolo contendere or its equivalent, shall not, of itself, create a presumption that the person did not act in good faith and in a manner which the person reasonably believed to be in or not opposed to the best interests of the corporation and, with respect to any criminal action or proceeding, had reasonable cause to believe that the person’s conduct was unlawful.

A corporation shall have the power to indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action or suit by or in the right of the corporation to procure a judgment in its favor by reason of the fact that the person is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise against expenses (including attorneys’ fees) actually and reasonably incurred by the person in connection with the defense or settlement of such action or suit if the person acted in good faith and in a manner the person reasonably believed to be in or not opposed to the best interests of the corporation and except that no indemnification shall be made in respect to any claim, issue or matter as to which such person shall have been adjudged to be liable to the corporation unless and only to the extent that the Court of Chancery or the court in which such action or suit was brought shall determine upon application that, despite the adjudication of liability but in view of all the circumstances of the case, such person is fairly and reasonably entitled to indemnity for such expenses which the Court of Chancery or such other court shall deem proper.

     As permitted by Delaware law, the Company has included in its restated certificate of incorporation a provision to eliminate the personal liability of its directors for monetary damages for breach of their fiduciary duties as directors, subject to certain exceptions. In addition, the Company’s restated certificate of incorporation provide that the Company is required to indemnify its officers and

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directors to the fullest extent authorized by the Delaware General Corporation Law. The Company is also required to indemnify its officers and directors in circumstances in which indemnification would otherwise be discretionary and the Company is required to advance expenses to its officers and directors as incurred in connection with proceedings against them for which they may be indemnified.

     The Company has entered into indemnification agreements with its directors and certain of its officers. Under the terms of the indemnification agreements, the Company has generally agreed to indemnify and advance expenses to the fullest extent permitted by applicable law on the date of such agreements and to such greater extent as applicable law may thereafter permit.

     The Company has obtained and intends to maintain directors and officers liability insurance covering all directors and officers of the Company against claims arising out of the performance of their duties.

Item 7. Exemption from Registration Claimed

     Not applicable.

Item 8. Exhibits

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Item 9. Undertakings

(a) The Company hereby undertakes:

     (1) To file, during any period in which offers or sales are being made, a post-effective amendment to this Registration Statement:

     (i) To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

     (ii) To reflect in the prospectus any facts or events arising after the effective date of the Registration Statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the Registration Statement;

     (iii) To include any material information with respect to the plan of distribution not previously disclosed in the Registration Statement or any material change to such information in the Registration Statement. Notwithstanding the foregoing, any increase or decrease in the volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20 percent change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective Registration Statement;

Provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply if the Registration Statement is on Form S-3 or Form S-8 and the information required to be included in a post-effective amendment by those paragraphs is contained in periodic reports filed with or furnished to the Commission by the Company pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the Registration Statement.

     (2) That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

     (3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(b) The Company hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the Company’s annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by

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reference in the Registration Statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(c) Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the Company pursuant to the foregoing provisions, or otherwise, the Company has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Company of expenses incurred or paid by a director, officer or controlling person of the Company in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Company will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Act and will be governed by the final adjudication of such issue.

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SIGNATURES

     Pursuant to the requirements of the Securities Act of 1933, the undersigned registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Minneapolis, State of Minnesota, on December 14, 2004.

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints THOMAS G. GRUDNOWSKI his or her attorney-in-fact, with full power of substitution, for him or her in any and all capacities, to sign any amendments, including post-effective amendments, to this Registration Statement on Form S-8 and to file the same, with exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, hereby ratifying and confirming all that said attorney-in-fact, or his substitute or substitutes, may do or cause to be done by virtue hereof. Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

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EXHIBIT INDEX

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Exhibit 5

FAEGRE & BENSON LLP

December 14, 2004

Fair Isaac Corporation
901 Marquette Avenue
Suite 3200
Minneapolis, Minnesota 55402

Ladies and Gentlemen:

     In connection with the Registration Statement on Form S-8 under the Securities Act of 1933, as amended (the “Registration Statement”), relating to an aggregate offering of 207,202 shares of Common Stock, par value $.01 per share (the “Shares”), of Fair Isaac Corporation, a Delaware corporation (the “Company”), to be issued by the Company pursuant to the Braun Consulting, Inc. 1998 Employee Long Term Stock Investment Plan, the Braun Consulting, Inc. 1998 Executive Long Term Stock Investment Plan, the Braun Consulting, Inc. 1999 Independent Director Stock Option Plan and the Braun Consulting, Inc. 2002 Employee Long Term Stock Investment Plan, as amended, we have examined such corporate records and other documents, including the Registration Statement, and have reviewed such matters of law as we have deemed relevant hereto, and, based upon such examination and review, it is our opinion that all necessary corporate action on the part of the Company has been taken to authorize the issuance and sale of the Shares and that, when issued and sold as contemplated in the Registration Statement, the Shares will be legally and validly issued, fully paid and nonassessable under the current laws of the State of Delaware.

     We are admitted to the practice of law in the State of Minnesota and the foregoing opinions are limited to the laws of that state and the federal laws of the United States of America.

     We consent to the filing of this opinion as an exhibit to the Registration Statement.

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Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

The Board of Directors
Fair Isaac Corporation:

We consent to the use of our report dated November 10, 2004, with respect to the consolidated balance sheets of Fair Isaac Corporation and subsidiaries as of September 30, 2004 and 2003, and the related consolidated statements of income, stockholders’ equity and comprehensive income and cash flows for each of the years in the three-year period ended September 30, 2004, incorporated herein by reference. Our report refers to a change in the Company’s method of accounting for goodwill in fiscal year 2003.

/s/ KPMG LLP

San Diego, California
December 13, 2004

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