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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

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                                   FORM 10-K/A
                                (AMENDMENT NO. 1)
                  ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d)
                     OF THE SECURITIES EXCHANGE ACT OF 1934
                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2001


                        COMMISSION FILE NUMBER: 33-64732

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


              DELAWARE                                     36-2815480
   (STATE OR OTHER JURISDICTION                (IRS EMPLOYER IDENTIFICATION NO.)
OF INCORPORATION OR ORGANIZATION)

                  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. ( )

         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
$16.85 ON MARCH 15, 2002, AND FOR THE PURPOSE OF THIS CALCULATION ONLY, THE
ASSUMPTION THAT ALL REGISTRANT'S DIRECTORS AND EXECUTIVE OFFICERS ARE
AFFILIATES) WAS APPROXIMATELY $157 MILLION.

         THE NUMBER OF SHARES OUTSTANDING OF THE REGISTRANT'S COMMON STOCK, PAR
VALUE $0.01, AS OF MARCH 15, 2002, WAS 16,877,721.

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                                EXPLANATORY NOTE


         SPSS Inc. ("SPSS") is filing this Amendment No. 1 on Form 10-K/A to
identify and correct typographical errors contained in SPSS's Annual Report on
Form 10-K for the fiscal year ended December 31, 2001 that was originally filed
with the Securities and Exchange Commission (the "SEC") on April 1, 2002 (the
"Original Filing").

         This report continues to speak as of the date of the Original Filing,
and SPSS has not updated the disclosure in this report to speak as of a later
date. While this report primarily relates to the historical period covered,
events may have taken place since the date of the Original Filing that might
have been reflected in this report if they had taken place prior to the Original
Filing. All information contained in this report and the Original Filing is
subject to updating and supplementing as provided in SPSS's periodic reports
filed with the SEC.

         The following summary identifies the location of each typographical
error contained in the Original Filing and a brief description of such
typographical error. However, we encourage you to read the pages following this
Explanatory Note for a more thorough discussion of each of the typographical
errors and how such typographical errors have been corrected.

         SPSS has made the following change in Item 6. Selected Consolidated
Financial Data:

         -    In the selected consolidated financial data table on page 17, SPSS
         has corrected the dollar amount for "Income (loss) before minority
         interest" identified in the December 31, 2000 column.

         SPSS has made the following changes in Item 7. Management's Discussion
and Analysis of Financial Condition and Results of Operations:

         -    In the paragraphs discussing Special General and Administrative
         Charges and Merger-related costs, SPSS has deleted and replaced two
         misspelled words.

         -    In the Liquidity and Capital Resources section, SPSS has moved the
         three paragraphs discussed under the heading "Summary Disclosures
         Regarding Related Parties" to another part of the Management's
         Discussion and Analysis section so that such discussion of "Summary
         Disclosures Regarding Related Parties" immediately follows the
         discussion of "International Operations."

         -    In the Liquidity and Capital Resources section, SPSS has corrected
         the dollar amount spent on net capital expenditures during fiscal 2000.

         -    In the Liquidity and Capital Resources section, SPSS has corrected
         (a) the dollar amount used in financing activities in 2001 and (b) the
         dollar amount of cash received from issuances of common stock through
         sales to a third party entity.

         -    In the Liquidity and Capital Resources section, SPSS has deleted
         an extraneous word from the fourth full paragraph on page 23.


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         SPSS has also made the following changes in Item 8. Financial
Statements and Supplementary Data:

         -    In the Consolidated Balance Sheets, SPSS has corrected the dollar
         amount for "Deferred income taxes" identified in the December 31, 2000
         column.

         -    In Note 2, SPSS has corrected (a) the dollar amount for other
         long-lived assets in the 2001 column and (b) the dollar amount for
         long-lived assets in all geographic regions in the 2001 column.

         -    In Note 9, SPSS has corrected (a) the dollar amount for other
         assets in the 2000 column and (b) the dollar amount for total other
         assets in the 2000 column.

         -    In Note 12, in the paragraphs discussing special general and
         administrative charges and merger-related costs, SPSS has deleted and
         replaced two misspelled words.

         - The footnote addressing Income Taxes should be identified as Note 13
         instead of Note 11.

         In Part III, Item 12, SPSS has deleted and correctly replaced (a) a
typographical error in the number of shares of common stock beneficially owned
by one of its outside directors and (b) a typographical error in the number of
options held by one of its executive officers as identified in footnote (12) to
the beneficial ownership table.

         In Part IV, Item 14, SPSS has provided the correct page number
cross-reference to the Consolidated Financial Statement Schedule.

         Any items in the Original Filing that are not expressly changed hereby
shall be as set forth in the Original Filing.



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ITEMIZED TYPOGRAPHICAL AMENDMENTS TO THE ANNUAL REPORT
ON FORM 10-K FOR THE FISCAL YEAR ENDED DECEMBER 31, 2001

ITEM 6. SELECTED CONSOLIDATED FINANCIAL DATA

         -    In the selected consolidated financial data table on page 17, the
         dollar amount for "Income (loss) before minority interest" in the
         December 31, 2000 column identified as "$4,234" in the Original Filing
         is hereby deleted and replaced with "$5,915."

ITEM 7. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
        OF OPERATIONS

         -    The word "dating" contained in the second sentence of the
         paragraph discussing Special General and Administrative charges is
         hereby deleted and replaced with the word "relating." (See first full
         paragraph on page 21)

         -    The word "several" contained in the third sentence of the
         paragraph discussing Merger-related costs is hereby deleted and
         replaced with the word "severance." (See second full paragraph on page
         21)

         -    On page 22 of the Liquidity and Capital Resources section, the
         heading "Summary Disclosures Regarding Related Parties" and the three
         paragraphs provided immediately under such heading, are hereby deleted
         from page 22 and moved to a new section on page 24, to be inserted
         immediately following the discussion of "International Operations."

         -    In the Liquidity and Capital Resources section, in the third
         sentence of the first full paragraph on page 23, the amount of cash
         used in net capital expenditures identified as "$12.7 million" in the
         Original Filing is hereby deleted and replaced with "$13.7 million."

         -    In the Liquidity and Capital Resources section, in the first
         sentence of the third full paragraph on page 23, the amount of cash
         used in financing activities in 2001 identified as "$9.3 million" in
         the Original Filing is hereby deleted and replaced with "$7.5 million."

         -    In the Liquidity and Capital Resources section, the last sentence
         of the third full paragraph on page 23 in the Original Filing is hereby
         deleted and replaced in its entirety with the following: "During 2001,
         $14.8 million in cash was used to repay borrowings under line-of-credit
         agreements, partially offset by $5.0 million provided primarily by an
         issuance of common stock through a sale to Siebel, and through employee
         exercises of stock options."

         -    In the first sentence of the fourth full paragraph on page 23, the
         word "million" following the number "$9,774,000" is hereby deleted.


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ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

         -    In the Consolidated Balance Sheets, the dollar amount for
         "Deferred income taxes" in the December 31, 2000 column identified as
         "$1,943" in the Original Filing is hereby deleted and replaced with
         "$749." (See page 32)

         -    In the third table of Note 2 (Domestic and Foreign Operations) to
         the Consolidated Financial Statements, (a) the amount of other
         long-lived assets identified as "$31,435,000" in the 2001 column of the
         Original Filing is hereby deleted and replaced with "$1,045,000"; and
         (b) the total amount of long-lived assets for all geographic regions
         identified as "$31,435,000" in the 2001 column of the Original Filing
         is hereby deleted and replaced with "$131,435,000." (See page 45)

         -    In the only table of Note 9 (Other Assets) to the Consolidated
         Financial Statements, (a) the amount of "other" assets identified as
         "$1,011,000" in the 2000 column of the Original Filing is hereby
         deleted and replaced with "$1,010,000"; and (b) the total amount of
         other assets identified as "$5,539,000" in the 2000 column of the
         Original Filing is hereby deleted and replaced with "$5,538,000." (See
         page 50)

         -    The word "dating" contained in the first full paragraph on page 52
         discussing special general and administrative charges is hereby deleted
         and replaced with the word "relating." (See Note 12 - Other Income
         (Expense) Special general and administrative charges, and Merger
         related costs)

         -    The word "several" contained in the second sentence of the second
         full paragraph on page 52 discussing merger-related expenses is hereby
         deleted and replaced with the word "severance." (See Note 12 - Other
         Income (Expense) Special general and administrative charges, and Merger
         related costs)

         -    The Note addressing "Income Taxes" should be "Note (13)" instead
         of "Note (11)" as identified in the Original Filing.

ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

         -    In the beneficial ownership table on page 74, the number of shares
         of SPSS common stock owned by Michael D. Blair identified as "34,101"
         shares in the Original Filing is hereby deleted and replaced with
         "34,099".

         -    With respect to the beneficial ownership table, the number of
         shares of SPSS common stock beneficially owned through options
         exercisable within 60 days by Patrick Dauga, identified as "23,334"
         shares in footnote (12) on page 75 of the Original Filing, is hereby
         deleted and replaced with "37,632."

ITEM 14. EXHIBITS, CONSOLIDATED FINANCIAL STATEMENT SCHEDULE, AND REPORTS ON
         FORM 8-K

         -    In paragraph (a)(2) on page 77, the cross-reference to the
         Consolidated Financial Statement Schedule identified as "page 58" in
         the Original Filing is hereby deleted and replaced with "page 61".

         -    In the exhibit table under (a)(3) on page 77, a new Exhibit 23.1
         (Consent of KPMG LLP) is being filed with this amendment.


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                                   SIGNATURES


         Pursuant to requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the Registrant has duly caused this report to be signed on
its behalf by the undersigned, thereunto duly authorized as of April 24, 2002.


                                            SPSS Inc.



                                            By:/s/ Edward Hamburg
                                               ---------------------------------
                                               Edward Hamburg
                                               Executive Vice President,
                                               Corporate Operations,
                                               Chief Financial Officer
                                               and Secretary