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                                                                   EXHIBIT 10.41


                                     WAIVER

         THIS WAIVER (this "AMENDMENT") is dated for reference purposes only as
of March 17, 2003, by and between Bank One, NA (as successor by merger to
American National Bank and Trust Company of Chicago), a national banking
association with its main office in Chicago, Illinois ("BANK"), and SPSS Inc., a
Delaware corporation ("Borrower").

                                    RECITALS:

         A. Bank has made loans and certain other financial accommodations to
Borrower pursuant to the terms of that certain Amended and Restated Loan
Agreement dated as of June 1, 2000, as amended by First Amendment to Amended and
Restated Loan Agreement dated as of January 26, 2001, the Waiver and Second
Amendment to Amended and Restated Loan Agreement dated as of May 31, 2002, the
Wavier and Third Amendment to Amended and Restated Loan Agreement dated as of
August 14, 2002 and the Waiver and Fourth Amendment to Amended and Restated Loan
Agreement dated as of November 13, 2002 (collectively, the "EXISTING LOAN
AGREEMENT").

         B. Borrower has failed to satisfy the requirements of Sections 6.1(a)
and 6.1(c) of the Existing Loan Agreement for the fiscal quarter ending December
31, 2002 (the "EXISTING DEFAULTS"), and Borrower has requested that Bank waive
the Existing Defaults.

         C. Bank has agreed to waive the Existing Defaults, subject to terms and
conditions of this Amendment.

NOW, THEREFORE, for good and valuable consideration, the receipt and sufficiency
of which are hereby acknowledged, the parties hereto agree as follows:

         1. Incorporation of Recitals. Borrower hereby represents and warrants
to Bank that the foregoing Recitals are (a) true and accurate, (b) an integral
part of this Amendment and (c) hereby incorporated into this Amendment and made
a part hereof. All terms capitalized but not expressly defined herein shall, for
purposes hereof, have the respective meanings set forth in the Existing Loan
Agreement.

         2. Waiver. Subject to the full completion of the conditions set forth
in Section 4, Bank hereby waives the Existing Defaults. Borrower and Bank hereby
agree that the foregoing waiver of the Existing Defaults shall in no way be
deemed to be a waiver or forbearance of any other default, any other Event of
Default or any Unmatured Default, whether now existing or hereafter arising,
under the Existing Loan Agreement or any other Loan Document.

         3. Effectiveness.

         (a) Borrower shall have executed and delivered to Bank a copy of this
Amendment.



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         (b) Borrower shall have repaid to the Bank the amount by which the
outstanding Loan balance exceeds $8,500,000.

         (c) Borrower shall have delivered to Bank a copy, certified by the
secretary of the Borrower, of the resolutions of Borrower's board of directors
authorizing the execution, delivery and performance of this Amendment.

         4. Post-closing Covenant. Borrower shall further take all action
requested by Bank, in its sole discretion, necessary or desirable to create in
favor of Bank a valid and perfected first priority pledge and security interest
in and to all of the capital stock of each Subsidiary of Borrower hereafter
identified by Bank to Borrower, and, in addition or in the alternative, as may
be directed by Bank in its sole discretion, to cause any such Subsidiary to
create in favor of Bank a valid and perfected first priority pledge and security
interest in and to all of such Subsidiary's assets. Borrower will also take such
further action with respect to perfecting Bank's existing security interests on
Borrower's assets as Bank may hereafter request. Any action requested by Bank
pursuant to this Section 5 shall be completed by Borrower within thirty (30)
days after Borrower's receipt of Bank's request.

         5. Expenses. Upon demand by Bank therefor, Borrower shall reimburse
Bank for all reasonable Costs, fees and expenses incurred by Bank or for which
Bank becomes obligated, in connection with the negotiation, preparation and
conclusion of this Amendment, including without limitation, reasonable
attorney's fees, costs and expenses, lien search fees, costs and expenses,
filing and recording fees and all taxes payable in connection with this
Amendment.

         6. Waiver of Claims. Borrower hereby acknowledges, agrees and affirms
that it possesses no claims, defenses, offsets, recoupment or counterclaims of
any kind or nature against or with respect to the enforcement of the Loan
Agreement or any other Loan Document or any amendments thereto (collectively,
the "Claims"), nor does Borrower now have knowledge of any facts that would or
might give rise to any Claims. If facts now exist which would or could give rise
to any Claim against or with respect to the enforcement of the Loan Agreement or
any other Loan Document, as amended by the amendments thereto, Borrower hereby
unconditionally, irrevocably and unequivocally waives and fully releases any and
all such Claims as if such Claims were the subject of a lawsuit, adjudicated to
final judgment from which no appeal could be taken and therein dismissed with
prejudice.

         7. Amendment. The Loan Documents and all rights and powers created
thereby and thereunder are in all respects ratified and confirmed and shall
remain in full force and effect, except as expressly modified hereby. From and
after the date hereof, (a) the Existing Loan Agreement shall be deemed to be
amended and modified as herein provided, but, except as so amended and modified,
the Existing Loan Agreement and this Amendment shall be read, taken and
construed as one and the same instrument and (b) the term "LOAN AGREEMENT" and
all references to amendments thereof as used in the Loan Documents shall mean
the Existing Loan Agreement as amended hereby.

         8. Jurisdictions. THIS AMENDMENT HAS BEEN DELIVERED FOR ACCEPTANCE BY
BANK IN CHICAGO, ILLINOIS AND SHALL BE GOVERNED BY



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AND CONSTRUED IN ACCORDANCE WITH THE INTERNAL LAWS (AS OPPOSED TO THE CONFLICTS
OF LAW PROVISIONS) OF THE STATE OF ILLINOIS. BORROWER HEREBY (i) IRREVOCABLY
SUBMITS, TO THE EXTENT PERMITTED BY APPLICABLE LAW, TO THE JURISDICTION OF ANY
STATE OR FEDERAL COURT LOCATED IN CHICAGO, ILLINOIS, OVER ANY ACTION OR
PROCEEDING TO ENFORCE OR DEFEND ANY MATTER ARISING FROM OR RELATED TO THIS
AMENDMENT; (ii) IRREVOCABLY WAIVES, TO THE FULLEST EXTENT BORROWER MAY
EFFECTIVELY DO SO, THE DEFENSE OF AN INCONVENIENT FORUM TO THE MAINTENANCE OF
ANY SUCH ACTION OR PROCEEDING IN ANY SUCH COURT; (iii) AGREES THAT, TO THE
EXTENT PERMITTED BY APPLICABLE LAW, A FINAL JUDGMENT IN ANY SUCH ACTION OR
PROCEEDING IN ANY SUCH COURT SHALL BE CONCLUSIVE AND MAY BE ENFORCED IN ANY
OTHER JURISDICTIONS BY SUIT ON THE JUDGMENT OR IN ANY OTHER MANNER PROVIDED BY
LAW; AND (iv) TO THE EXTENT PERMITTED BY APPLICABLE LAW, BORROWER AGREES NOT TO
INSTITUTE ANY LEGAL ACTION OR PROCEEDING AGAINST BANK OR ANY OF BANK'S
DIRECTORS, OFFICERS, EMPLOYEES, AGENTS OR PROPERTY, CONCERNING ANY MATTER
ARISING OUT OF OR RELATING TO THIS AMENDMENT IN ANY COURT OTHER THAN ANY STATE
OR FEDERAL COURT LOCATED IN COOK COUNTY, ILLINOIS. NOTHING IN THIS SECTION SHALL
AFFECT OR IMPAIR BANK'S RIGHT TO SERVE LEGAL PROCESS IN ANY MANNER PERMITTED BY
LAW OR BANK'S RIGHT TO BRING ANY ACTION OR PROCEEDING AGAINST BORROWER OR
BORROWER'S PROPERTY IN THE COURTS OF ANY OTHER JURISDICTION.

         9. Trial by Jury. TO THE EXTENT PERMITTED BY LAW, BORROWER AND BANK
EACH HEREBY KNOWINGLY, VOLUNTARILY AND INTENTIONALLY WAIVES THE RIGHT TO A TRIAL
BY JURY IN RESPECT OF ANY LITIGATION BASED HEREON, ARISING OUT OF, UNDER OR IN
CONNECTION WITH THIS AMENDMENT OR ANY COURSE OF CONDUCT, COURSE OF DEALINGS,
STATEMENTS (WHETHER VERBAL OR WRITTEN) OR ACTIONS OF EITHER PARTY IN CONNECTION
HEREWITH. BORROWER HEREBY EXPRESSLY ACKNOWLEDGES THAT THIS WAIVER IS A MATERIAL
INDUCEMENT FOR BANK TO MAKE THE LOANS.

         10. Representations. This Amendment shall be binding upon and inure to
the benefit of the parties hereby and their respective successors and assigns.
To induce Bank to enter into this Amendment, Borrower hereby represents and
warrants to Bank that:

                  (a) the execution and delivery of this Amendment, and the
         performance by Borrower of its obligations under this Amendment and the
         other Loan Documents as amended, are within Borrower's corporate
         powers, have been duly authorized by all necessary corporate action,
         have received all necessary governmental approval (if any shall be
         required) and do not and will not contravene or conflict with any
         provisions of law or the Articles of Incorporation or By-Laws of
         Borrower or of any other agreement binding upon Borrower;



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                  (b) this Amendment, and each other instrument executed by
         Borrower concurrently herewith, is the legal, valid and binding
         obligation of Borrower, enforceable against Borrower in accordance with
         their respective terms, except as enforcement thereof may be subject to
         the effect of applicable bankruptcy, insolvency, reorganization,
         moratorium or similar laws affecting creditors' rights generally, and
         to the general principles of equity (regardless of whether such
         enforcement is sought in a proceeding in equity or at law);

                  (c) all of the representations and warranties of Borrower made
         in the Loan Documents are true and correct as of the date hereof,
         except where such representation or warranty specifically relates to an
         earlier date;

                  (d) as of the date hereof, after giving effect to this
         Amendment, no Event of Default or Unmatured Default under the Loan
         Documents exists; and

                  (e) this Amendment, the Existing Loan Agreement and each and
         every Other Agreement shall be a "credit agreement" under the Illinois
         Credit Agreements Act, 815 ILCS 160/1 et.seq. (the "ACT"), the Act
         applies to this transaction and any action on or in any way related to
         each and every Loan Document shall be governed by the Act


         IN WITNESS WHEREOF, the parties hereto have caused this Amendment dated
for reference purposes only as of March 17, 2003.


                                        SPSS INC.


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

                                        BANK ONE, NA


                                        By:      /s/ Shane E. Green
                                                 -------------------
                                        Title:   Assistant Vice President
                                                 -------------------------


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