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                                                                    EXHIBIT 15.1



                          ACKNOWLEDGMENT OF INDEPENDENT
                          CERTIFIED PUBLIC ACCOUNTANTS
                  REGARDING INDEPENDENT AUDITORS' REVIEW REPORT


The Board of Directors
SPSS Inc.:

With respect to the registration statements on Form S-8 (nos. 333-25869,
33-73130, 33-80799, 33-73120, 333-63167 and 33-74402), on Form S-3 (nos.
333-41207, 333-21025, 333-10423 and 333-30460) and on Form S-4 (no. 333-15427)
of SPSS Inc., we acknowledge our awareness of the use therein of our report
dated August 4, 2000 related to our review of interim financial information.

Pursuant to Rule 436(c) under the Securities Act of 1933, such report is not
considered part of a registration statement prepared or certified by an
accountant or a report prepared or certified by an accountant within the meaning
of sections 7 and 11 of the Act.



                                               /s/ KPMG LLP



Chicago, Illinois
August 11, 2000