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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                 ---------------

                                   FORM 10-K/A
                                (AMENDMENT NO. 2)

                  ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d)
                     OF THE SECURITIES EXCHANGE ACT OF 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2004

                        COMMISSION FILE NUMBER: 33-64732

                                 ---------------

                                    SPSS INC.
             (Exact name of registrant as specified in its charter)

                 DELAWARE                              36-2815480
     (State or other jurisdiction of                 (IRS Employer
     incorporation or organization)                Identification No.)

                  233 S. WACKER DRIVE, CHICAGO, ILLINOIS 60606
              (Address of principal executive offices and zip code)

               REGISTRANT'S TELEPHONE NUMBER INCLUDING AREA CODE:
                                 (312) 651-3000

           SECURITIES REGISTERED PURSUANT TO SECTION 12(b) OF THE ACT:
                                      NONE

           SECURITIES REGISTERED PURSUANT TO SECTION 12(g) OF THE ACT:
                     COMMON STOCK, PAR VALUE $.01 PER SHARE
                                (Title of Class)

      Indicate by check mark whether the registrant (1) has filed all reports 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 filing requirements
for the past 90 days. Yes [X] No [ ]

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

      Indicate by check mark whether the registrant is an accelerated filer (as
defined in Exchange Act Rule 12b-2). Yes [X] No [ ]

      The aggregate market value of the registrant's voting stock held by
non-affiliates of the registrant (based upon the per share closing sale price of
$17.97 on June 30, 2004) was approximately $315.8 million.

      The number of shares outstanding of the registrant's Common Stock, par
value $0.01, as of March 1, 2005, was 17,783,279.

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EXPLANATORY NOTE

      SPSS Inc. ("SPSS" or the "Company") filed its Annual Report on Form 10-K
for fiscal year 2004 (the "Annual Report") with the Securities and Exchange
Commission (the "Commission") on March 16, 2005 and amended the Annual Report by
filing Amendment No. 1 to Annual Report on Form 10-K with the Commission on
April 22, 2005. This Amendment No. 2 to Annual Report on Form 10-K ("Amendment
No. 2") amends the Annual Report solely to incorporate by reference a revised
redacted version of Exhibit 10.50 that conforms with specifications requested by
the Commission in response to the Company's request for confidential treatment.
This revised redacted version of Exhibit 10.50 is incorporated into this
Amendment No. 2 by reference to the revised redacted version of the agreement
made publicly available by SPSS on a Form 8-K filed with the Commission on
January 20, 2006. Accordingly, Exhibit 10.50 is hereby amended and restated in
its entirety. In accordance with Rule 12b-15 promulgated under the Securities
Exchange Act of 1934, as amended (the "Exchange Act"), SPSS has included in this
Amendment No. 2 only Item 15 of Part IV of Form 10-K. The remainder of the
information contained in the Annual Report, as amended by Amendment No. 1, is
not amended hereby. This Amendment No. 2 does not reflect events occurring after
the filing of the Annual Report, as amended by Amendment No. 1, or modify or
update the disclosures contained in either document in any way other than as
required to reflect the amendment set forth below. In connection with the filing
of this Amendment No. 2 and pursuant to the Commission rules promulgated
pursuant to the Exchange Act, SPSS is including with this Amendment No. 2
certain currently dated certifications.

                                       1
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ITEM 15.  EXHIBITS AND CONSOLIDATED FINANCIAL STATEMENT SCHEDULE

    (a)(1) Consolidated Financial Statements commence on page 39:

      Consolidated Balance Sheets as of December 31, 2003 and 2004

      Consolidated Statements of Operations for the years ended December 31,
      2002, 2003 and 2004

      Consolidated Statements of Comprehensive Income (Loss) for the years ended
      December 31, 2002, 2003 and 2004

      Consolidated Statements of Stockholders' Equity for the years ended
      December 31, 2002, 2003 and 2004

      Consolidated Statements of Cash Flows for the years ended December 31,
      2002, 2003 and 2004

      Notes to Consolidated Financial Statements

    (2) Consolidated Financial Statement Schedule -- see page 72:

      Schedule II Valuation and qualifying accounts

      Schedules not filed:

      All schedules other than that indicated in the index have been omitted as
      the required information is inapplicable or the information is presented
      in the consolidated financial statements or related notes.

    (3) Exhibits required by Item 601 of Regulation S-K. (Note: Management
        contracts and compensatory plans or arrangements are identified with
        a "+" in the following list.)

<TABLE>
<CAPTION>
                                                                                      INCORPORATION
EXHIBIT                                                                               BY REFERENCE
NUMBER                               DESCRIPTION OF DOCUMENT                          (IF APPLICABLE)
-------                              -----------------------                          ---------------
<S>      <C>                                                                          <C>
   2.1   Agreement and Plan of Merger among SPSS Inc., SPSS ACSUB, Inc., Clear         (1), Ex. 2.1
         Software, Inc. and the shareholders named therein, dated September 23,
         1996.

   2.2   Agreement and Plan of Merger among SPSS Inc., SPSS Acquisition Inc. and       (2), Annex A
         Jandel Corporation, dated October 30, 1996.

   2.3   Asset Purchase Agreement by and between SPSS Inc. and DeltaPoint, Inc.,       (14), Ex. 2.3
         dated as of May 1, 1997.

   2.4   Stock Purchase Agreement among the Registrant, Edward Ross, Richard           (3), Ex. 2.1
         Kottler, Norman Grunbaum, Louis Davidson and certain U.K.-Connected
         Shareholders or warrant holders of Quantime Limited named therein,
         dated as of September 30, 1997, together with a list briefly
         identifying the contents of omitted schedules.

   2.5   Stock Purchase Agreement among the Registrant, Edward Ross, Richard           (3), Ex. 2.2
         Kottler, Norman Grunbaum, Louis Davidson and certain Non-U.K.
         Shareholders or warrant holders of Quantime Limited named therein,
         dated as of September 30, 1997, together with a list briefly
         identifying the contents of omitted schedules.
</TABLE>

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<TABLE>
<S>      <C>                                                                           <C>
2.6      Stock Purchase Agreement by and among SPSS Inc. and certain                   (4), Ex. 2.1
         Shareholders of Quantime Limited listed on the signature pages thereto,
         dated November 21, 1997.

2.7      Stock Purchase Agreement by and among Jens Nielsen, Henrik Rosendahl,         (4), Ex. 2.2
         Ole Stangegaard, Lars Thinggaard, Edward O'Hara, Bjorn Haugland, 2M
         Invest and the Shareholders listed on Exhibit A thereto, dated November
         21, 1997.

2.8      Stock Purchase Agreement by and among SPSS Inc. and the Shareholders of       (15), Ex. 2.1
         Integral Solutions Limited listed on the signature pages hereof, dated
         as of December 31, 1998.

2.9      Share Purchase Agreement by and among SPSS Inc., Surveycraft Pty Ltd.         (17), Ex. 2.9
         and Jens Meinecke and Microtab Systems Pty Ltd., dated as of November
         1, 1998.

2.10     Stock Acquisition Agreement by and among SPSS Inc., Vento Software,           (18), Ex. 2.1
         Inc. and David Blyer, John Gomez and John Pappajohn, dated as of
         November 29, 1999.

2.11     Asset Purchase Agreement by and between SPSS Inc. and DataStat, S.A.,         (20), Ex. 2.11
         dated as of December 23, 1999.

2.12     Agreement and Plan of Merger dated as of November 6, 2000, among SPSS         (21), Ex. 2.1
         Inc., SPSS Acquisition Sub Corp., and ShowCase Corporation.

2.13     Agreement and Plan of Merger dated as of October 28, 2001, among SPSS         (24), Ex. 99.1
         Inc., Red Sox Acquisition Corp. and NetGenesis Corp.

2.14     Stock Purchase Agreement by and among SPSS Inc., LexiQuest, S.A. and          (26), Ex. 2.14
         the owners of all of the issued and outstanding shares of capital stock
         of LexiQuest, S.A., dated as of January 31, 2002.

2.15     Stock Purchase Agreement, dated as of November 4, 2003, by and among          (30), Ex. 2.15
         SPSS Inc., SPSS International B.V. and the owners of all of the issued
         and outstanding shares of Data Distilleries B.V. identified on Exhibit
         A thereto.

3.1      Certificate of Incorporation of SPSS.                                         (5), Ex. 3.2

3.2      By-Laws of SPSS.                                                              (5), Ex. 3.4

4.1      Intentionally Omitted.

4.2      Amended and Restated Rights Agreement, dated as of August 31, 2004, by        (32), Ex. 4.2
         and between SPSS Inc. and Computershare Investor Services, LLP, as
         Rights Agent.

</TABLE>

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<TABLE>
<S>      <C>                                                                            <C>
10.1     Employment Agreement with Jack Noonan.+                                        (7), Ex. 10.1

10.2     Agreement with Valletta.+                                                      (6), Ex. 10.2

10.3     Agreement between SPSS and Prentice Hall.                                      (6), Ex. 10.5

10.4     Intentionally omitted.

10.5     HOOPS Agreement.                                                               (6), Ex. 10.7

10.6     Stockholders Agreement.                                                        (5), Ex. 10.8

10.7     Agreements with CSDC.                                                          (5), Ex. 10.9

10.8     Amended 1991 Stock Option Plan.+                                               (5), Ex. 10.10

10.9     SYSTAT Asset Purchase Agreement.                                               (8), Ex. 10.9

10.10    Intentionally Omitted.

10.11    Lease for Chicago, Illinois Office.                                            (9), Ex. 10.12

10.12    Amendment to Lease for Chicago, Illinois Office.                               (9), Ex. 10.13

10.13    1995 Equity Incentive Plan.+                                                  (10), Ex. 10.14

10.14    Intentionally Omitted.

10.15    Amended and Restated 1995 Equity Incentive Plan.+                             (11), Ex. 10.17

10.16    Intentionally Omitted.

10.17    Software Distribution Agreement between the Company and Banta Global          (12), Ex. 10.19
         Turnkey.

10.18    Lease for Chicago, Illinois in Sears Tower.                                   (13), Ex. 10.20

10.19    Intentionally Omitted.

10.20    Intentionally Omitted.
</TABLE>

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<TABLE>
<S>      <C>                                                                           <C>
10.21    Second Amended and Restated 1995 Equity Incentive Plan.+                      (16), Ex. A

10.22    Intentionally Omitted.

10.23    Third Amended and Restated 1995 Equity Incentive Plan.+                       (19), Ex. 10.1

10.24    Intentionally Omitted.

10.25    Intentionally Omitted.

10.26    Intentionally Omitted.

10.27    2000 Equity Incentive Plan.+                                                  (22), Ex. 10.45

10.28    SPSS Qualified Employee Stock Purchase Plan.+                                 (22), Ex. 10.46

10.29    SPSS Nonqualified Employee Stock Purchase Plan.+                              (22), Ex. 10.47

10.30    Intentionally Omitted.

10.31    Stock Purchase Agreement by and between SPSS Inc. and Siebel Systems, Inc.    (23), Ex. 10.31

10.32    1999 Employee Equity Incentive Plan.+                                         (25), Ex. 4.1

10.33    Intentionally Omitted.

10.34    Intentionally Omitted.

10.35    Intentionally Omitted.

10.36    Intentionally Omitted.

10.37    Intentionally Omitted.

10.38    Intentionally Omitted.

10.39    Intentionally Omitted.

10.40    Intentionally Omitted.

10.41    Intentionally Omitted.
</TABLE>

                                       5
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<TABLE>
<S>      <C>                                                                       <C>
10.42    Intentionally Omitted.

10.43    Loan and Security Agreement, dated as of March 31, 2003, by and between   (27), Ex. 10.43
         SPSS Inc. and each SPSS subsidiary that may become additional
         borrowers, as Borrower, and Foothill Capital Corporation, as Lender.

10.44    Amendment to Stock Purchase Agreement, dated as of October 1, 2003, by    (28), Ex. 10.44
         and between SPSS Inc. and America Online, Inc.

10.45    Amended and Restated Strategic Online Research Services Agreement,        (28), Ex. 10.45
         dated as of October 1, 2003, by and between SPSS Inc. and America
         Online, Inc.

10.46    Consulting Agreement, dated as of June 1, 2003, by and between SPSS       (29), Ex. 10.46
         Inc. and Norman H. Nie Consulting, L.L.C.

10.47    SPSS Inc. Amended and Restated 2002 Equity Incentive Plan.                (33), Ex. 10.47

10.48    Amended and Restated Employment Agreement, dated as of August 16, 2004,
         by and between SPSS Inc. and Raymond H. Panza.

10.49    Employment Agreement, dated as of August 16, 2004, by and between SPSS
         Inc. and Edward Hamburg.

10.50    OEM Agreement, dated as of November 5, 2004, by and between SPSS Inc.     (34), Ex. 10.50
         and Hyperion Solutions Corporation.*

10.51    Amended and Restated Consulting Agreement, dated as of January 1, 2005,
         by and between SPSS Inc. and Norman H. Nie Consulting, L.L.C.

10.52    Amended and Restated Employment Agreement, dated as of March 1, 2005,
         by and between SPSS Inc. and Jack Noonan.

14.1     SPSS Inc. Code of Business Conduct and Ethics.                            (31), Ex. 14.1

21.1     Subsidiaries of SPSS Inc.

23.1     Consent of KPMG LLP.

31.1     Certification of the Chief Executive Officer and President pursuant to
         Section 302 of the Sarbanes-Oxley Act of 2002.

31.2     Certification of the Chief Financial Officer pursuant to Section 302 of
         the
</TABLE>

                                       6
<PAGE>

<TABLE>
<S>      <C>                                                                       <C>
         Sarbanes-Oxley Act of 2002.

32.1     Certification of the Chief Executive Officer and President pursuant to
         18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the
         Sarbanes-Oxley Act of 2002.

32.2     Certification of the Chief Financial Officer pursuant to 18 U.S.C.
         Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley
         Act of 2002.

99.1     SPSS Inc. Charter of the Audit Committee of the Board of Directors.       (31), Ex. 99.1

99.2     Supplement A to the SPSS Inc. Charter of the Audit Committee of the       (31), Ex. 99.2
         Board of Directors.
</TABLE>

-----------------
*     Portions of this Exhibit are omitted and have been filed separately with
      the Securities and Exchange Commission in connection with a pending
      request for confidential treatment of certain portions of the Exhibit
      pursuant to Rule 24b-2 under the Securities Exchange Act of 1934.

(1)   Previously filed with the Report on Form 8-K of SPSS Inc., dated September
      26, 1996, filed on October 11, 1996, as amended on Form 8-K/A-1, filed
      November 1, 1996. (File No. 000-22194)

(2)   Previously filed with Amendment No. 1 to the Registration Statement on
      Form S-4 of SPSS Inc. filed on November 7, 1996. (File No. 333-15427)

(3)   Previously filed with the Report on Form 8-K of SPSS Inc., dated September
      30, 1997, filed on October 15, 1997. (File No. 000-22194)

(4)   Previously filed with the Registration Statement on Form S-3 of SPSS Inc.
      filed on November 26, 1997. (File No. 333-41207)

(5)   Previously filed with Amendment No. 2 to the Registration Statement on
      Form S-1 of SPSS Inc. filed on August 4, 1993. (File No. 33-64732)

(6)   Previously filed with Amendment No. 1 to the Registration Statement on
      Form S-1 of SPSS Inc. filed on July 23, 1993. (File No. 33-64732)

(7)   Previously filed with the Registration Statement on Form S-1 of SPSS Inc.
      filed on June 22, 1993. (File No. 33-64732)

(8)   Previously filed with the Registration Statement on Form S-1 of SPSS Inc.
      filed on December 5, 1994. (File No. 33-86858)

(9)   Previously filed with the Annual Report on Form 10-K of SPSS Inc. for the
      year ended December 31, 1994. (File No. 000-22194)

(10)  Previously filed with the 1995 Proxy Statement of SPSS Inc. (File No.
      000-22194)

(11)  Previously filed with the 1996 Proxy Statement of SPSS Inc. (File No.
      000-22194)

                                       7
<PAGE>

(12)  Previously filed with the Annual Report on Form 10-K of SPSS Inc. for the
      year ended December 31, 1996. (File No. 000-22194)

(13)  Previously filed with the Quarterly Report on Form 10-Q of SPSS Inc. for
      the quarterly period ended March 31, 1997. (File No. 000-22194)

(14)  Previously filed with the Quarterly Report on Form 10-Q of SPSS Inc. for
      the quarterly period ended June 30, 1997. (File No. 000-22194)

(15)  Previously filed with the Report on Form 8-K of SPSS Inc., dated December
      31, 1998, filed on January 15, 1999, as amended on Form 8-K/A filed March
      12, 1999. (File No. 000-22194)

(16)  Previously filed with the 1998 Proxy Statement of SPSS Inc. (File No.
      000-22194)

(17)  Previously filed with the Annual Report on Form 10-K of SPSS Inc. for the
      year ended December 31, 1998. (File No. 000-22194)

(18)  Previously filed with the Report on Form 8-K of SPSS Inc., dated November
      29, 1999, filed December 10, 1999. (File No. 000-22194)

(19)  Previously filed with the Quarterly Report on Form 10-Q of SPSS Inc. for
      the quarterly period ended June 30, 1999. (File No. 000-22194)

(20)  Previously filed with the Annual Report on Form 10-K of SPSS Inc. for the
      year ended December 31, 1999. (File No. 000-22194)

(21)  Previously filed with the Report on Form 8-K of SPSS Inc., filed November
      15, 2000. (File No. 000-22194)

(22)  Previously filed with the Registration Statement on Form S-4 of SPSS Inc.,
      filed on December 19, 2000. (File No. 333-52216)

(23)  Previously filed with Registration Statement on the Form S-3 of SPSS Inc.
      filed on October 9, 2001. (File No. 333-71236)

(24)  Previously filed with the Report on Form 8-K of SPSS Inc., dated October
      28, 2001, filed on October 29, 2001. (File No. 000-22194)

(25)  Previously filed with the Registration Statement on Form S-8 of SPSS Inc.
      filed on September 15, 2000. (File No. 333-45900)

(26)  Previously filed with the Report on Form 8-K of SPSS Inc., dated February
      6, 2002, filed on February 21, 2002. (File No. 000-22194)

(27)  Previously filed with the Annual Report on Form 10-K of SPSS Inc. for the
      year ended December 31, 2002. (File No. 000-22194)

(28)  Previously filed with the Report on Form 8-K of SPSS Inc., dated October
      1, 2003, filed on October 15, 2003. (File No. 000-22194)

                                       8
<PAGE>

(29)  Previously filed with the Quarterly Report on Form 10-Q of SPSS Inc. for
      the quarterly period ended September 30, 2003. (File No. 000-22194)

(30)  Previously filed with the Report on Form 8-K of SPSS Inc., dated November
      5, 2003, filed on November 18, 2003. (File No. 000-22194)

(31)  Previously filed with the Annual Report on Form 10-K of SPSS Inc. for the
      year ended December 31, 2003. (File No. 000-22194)

(32)  Previously filed with the Registration Statement on Form 8-A12G/A of SPSS
      Inc. filed on August 31, 2004. (File No. 000-22194)

(33)  Previously filed with the Registration Statement on Form S-8 of SPSS Inc.
      filed on October 29, 2004. (File No. 222-120066)

(34)  Previously filed with the Current Report on Form 8-K/A (Amendment No. 2)
      filed January 20, 2006. (File No. 000-22194)

                                       9
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                                   SIGNATURES

      Pursuant to requirements of Section 13 or 15(d) of the Securities Exchange
Act of 1934 and Rule 12b-15 promulgated thereunder, the Registrant has duly
caused this Amendment No. 2 to Annual Report on Form 10-K to be signed on its
behalf by the undersigned, thereunto duly authorized as of January 20, 2006.

                       SPSS INC.

                       By: /s/ Raymond H. Panza
                           ----------------------------------
                           Raymond H. Panza
                           Executive Vice President, Corporate Operations, Chief
                           Financial Officer and Secretary

                                       10
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                                 EXHIBIT INDEX

<TABLE>
<CAPTION>
EXHIBIT
NUMBER                               DOCUMENT DESCRIPTION
-------                              --------------------
<S>       <C>
  31.1    Certification of the Chief Executive Officer and President pursuant to
          Section 302 of the Sarbanes-Oxley Act of 2002.

  31.2    Certification of the Chief Financial Officer pursuant to Section 302
          of the Sarbanes-Oxley Act of 2002.

  32.1    Certification of Chief Executive Officer and President pursuant to 18
          U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the
          Sarbanes-Oxley Act of 2002.

  32.2    Certification of Chief Financial Officer pursuant to 18 U.S.C. Section
          1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of
          2002.
</TABLE>

                                       11