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                                                                   EXHIBIT 10.49

                              EMPLOYMENT AGREEMENT

      This Employment Agreement (this "Agreement"), dated December 7, 2004,
effective as of August 16, 2004, is by and between SPSS Inc. ("Employer") and
Edward Hamburg (hereinafter "Employee"). In consideration of the agreements and
provisions contained herein, Employer and Employee hereby agree as follows:

1.    Employee resigned from his position as Executive Vice President, Corporate
      Operations, Chief Financial Officer and Secretary (the "Resignation") of
      Employer, effective as of August 16, 2004 (the "Resignation Effective
      Date"), and Employer accepted Employee's Resignation as of the Resignation
      Effective Date. Employee and Employer agree that, following the
      Resignation Effective Date, Employee has been employed as and will
      continue to be employed as an Executive Vice President of Employer through
      December 31, 2004, at which time Employee shall resign his position as an
      officer of Employer.

2.    Employer agrees to employ the Employee, effective as of January 1, 2005,
      in an executive staff position at the Employer, and Employee shall accept
      employment as an employee of Employer in an executive staff position (the
      "Position") during the term of this Agreement and subject to the terms of
      this Agreement. The term of the Position shall commence and Employee's
      employment as an employee of Employer in an executive staff position shall
      commence on January 1, 2005 and shall terminate on January 31, 2007 or any
      earlier date arising pursuant to Section 4 below (the "Position Term"),
      and Employee waives the right to continued employment or rehiring after
      such date. During the Position Term, Employee shall report directly to the
      Company's Chief Executive officer.

3.    In full consideration for all of the services rendered by Employee during
      the Position Term and in lieu of any other payments owed to Employee:

      (a)   Employee shall receive a monthly salary as follows:

            (i)   From August 16, 2004 through January 31, 2005, Employee shall
                  receive the regular monthly base salary to which he was
                  entitled in his position as the Executive Vice President,
                  Corporate Operations, Chief Financial Officer and Secretary of
                  the Company, payable in regular installments in accordance
                  with Employer's general payroll practices and subject to
                  customary withholding; and

            (ii)  From February 1, 2005 through the end of the Position Term,
                  Employee shall receive a monthly salary in the amount of
                  $17,625 per month (the "Monthly Salary"), payable in regular
                  installments in accordance with Employer's general payroll
                  practices and subject to customary withholding.

      (b)   Employee will be eligible for bonuses for the fiscal quarters ended
            September 30, 2004 and December 31, 2004, which bonuses shall be
            based on Employer's management bonus plan for 2004 and shall be
            subject to approval by the Employer's Board of Directors if 2004
            bonuses for the Employer's other executive officers are subject to
            Board approval. Unless otherwise determined by Employer, Employee
            will not be eligible for bonuses with regard to any fiscal quarter
            ended after December 31, 2004.

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      (c)   Unless terminated for Cause (as defined in Section 4(a) below) or
            Employee accepts a position either full or part-time with another
            organization or starts his own company, Employee shall receive the
            following benefits:

            (i)   From August 16, 2004 through the end of the Position Term,
                  Employee will be eligible for the then current benefit program
                  of Employer offered to other employees.

            (ii)  Following the end of the Position Term, Employee shall be
                  responsible for paying all of Employee's own COBRA expenses,
                  and only those benefits covered by COBRA shall be available to
                  Employee.

      (d)   Employee's stock options shall be exercisable in accordance with the
            terms of the applicable stock option agreement. For purposes of each
            of Employee's stock option agreements, Employee shall be an employee
            throughout the Position Term. At the sole discretion of Employer,
            Employee may continue to participate in Employer's employee stock
            option program throughout the Position Term.

      (e)   If Employee or Employer terminates Employee's Staff Position for any
            reason other than pursuant to 4(a) below, upon termination of the
            Position Term, Employee shall receive, as his sole severance
            benefit, a severance payment in an amount equal to all of the salary
            payments that would otherwise be payable to Employee pursuant to
            Section 3(a) hereof from the effective date of such termination
            through January 31, 2007, subject to required withholding, provided
            that Employee, at such time, executes and delivers to Employer a
            release in the form set forth in Sections 8 and 9 hereof and abides
            by the terms of the noncompetition agreement referred to in Section
            6 hereof.

4.    The Position Term may be terminated prior to January 31, 2007 as follows:

      (a)   By the Employer for Cause. For purposes of this Agreement, "Cause"
            shall mean any deliberate act which causes harm to Employer,
            including without limitation, theft, fraud or intentional damage to
            the Employer's reputation. If Employer terminates the Position Term
            pursuant to this Section 4(a), Employee shall not be entitled to any
            salary payments that would otherwise be payable to Employee pursuant
            to Section 3(a) for any months following the effective date of such
            termination or any other compensation, benefits or severance under
            this Agreement (except for COBRA coverage, which will be available
            to Employee at his own cost).

      (b)   By the Employer or Employee without Cause: (i) upon mutual written
            agreement; or (ii) if Employee accepts a position either full or
            part-time with another organization or starts his own company.

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5.    Change of Control.

      (a)   Definitions. For purposes of this Section 5, the following terms
            shall be defined as follows:

            (i)   "Cause" shall have the meaning ascribed to such term in
                  Section 4(a) above.

            (ii)  "Change of Control" shall mean any one or more of the
                  following: (i) the accumulation, by any individual, entity or
                  group (within the meaning of Section 13(d)(3) or 14(d)(2) of
                  the Securities Exchange Act of 1934, as amended (the "Exchange
                  Act")) not previously owning common stock of the Company, of
                  fifteen percent (15%) or more of the shares of the then
                  outstanding common stock of Employer (the "Outstanding Common
                  Stock"), (ii) a merger or consolidation of Employer in which
                  Employer does not survive as an independent public company,
                  (iii) a sale of all or substantially all of the assets of
                  Employer, (iv) a triggering event under that certain Amended
                  and Restated Rights Agreement, dated as of August 31, 2004, by
                  and between Employer and Computershare Investor Services, LLC
                  or any amendment, restatement or replacement thereof, or (v) a
                  liquidation or dissolution of Employer; provided, however,
                  that the following acquisitions shall not constitute a Change
                  of Control for the purposes of this Agreement: (i) any
                  acquisitions of common stock or securities convertible into
                  common stock directly from Employer, or (ii) any acquisition
                  of common stock or securities convertible into common stock by
                  any employee benefit plan (or related trust) sponsored or
                  maintained by Employer.

            (iii) "Effective Date" shall mean the date on which a Change of
                  Control becomes effective.

            (iv)  "Surviving Entity" shall mean the entity surviving a
                  transaction between Employer and another company (with the
                  term "company" to include but not be limited to any
                  individual, group of individuals, partnership, corporation, or
                  other similar entities).

      (b)   Change of Control. Effective as of August 16, 2004 through the
            termination of the Position Term, in the event of a Change of
            Control, the following provisions shall apply:

            (i)   Continuation of Employee's Employment by Surviving Entity. If,
                  upon the Effective Date of a Change of Control, the Surviving
                  Entity continues Employee's employment, the terms of this
                  Agreement shall continue in full force and effect, and
                  Employee shall be entitled to all rights and benefits
                  hereunder.

            (ii)  Termination of Employee's Employment by Surviving Entity. If,
                  upon the Effective Date of a Change of Control, or within
                  twelve (12) months thereafter, the Surviving Entity terminates
                  the Employee's employment without Cause, the Employee shall be
                  entitled to the following benefits:

                  (A)   Salary/Benefits. Employee shall be entitled to all
                        salary payments and

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                        benefits to which Employee would otherwise be entitled
                        under this Agreement if Employee was terminated without
                        Cause prior to the Change of Control.

                  (B)   Treatment of Stock Options, Restricted Stock and Stock
                        Appreciation Rights upon Change of Control

                        (1)   Change of Control in a Transaction with a Private
                              Company. In the event a Change of Control occurs
                              as the result of a transaction between Employer
                              and a company whose common stock is not publicly
                              traded on a domestic national stock exchange, the
                              NASDAQ national market, or their respective
                              successors or equivalents (a "Private Company"),
                              then:

                              (a)   all of Employee's stock options (vested and
                                    unvested) granted by Employer prior to the
                                    Effective Date (1) shall be deemed to be
                                    fully exercisable upon the Effective Date
                                    and (2) shall be cashed out at the
                                    transaction value as calculated as of the
                                    Effective Date less the exercise price of
                                    such stock options and paid by the Surviving
                                    Entity to Employee on or within thirty (30)
                                    days following the Effective Date;

                              (b)   all restrictions on transferability of
                                    restricted stock held by the Employee on the
                                    Effective Date shall be deemed to have
                                    terminated immediately prior to the
                                    Effective Date; and

                              (c)   all of the stock appreciation rights (vested
                                    and unvested) granted by Employer prior to
                                    the Effective Date (1) shall be deemed to be
                                    fully exercisable upon the Effective Date
                                    and (2) shall be cashed out at the
                                    transaction value as calculated as of the
                                    Effective Date and paid by the Surviving
                                    Entity to Employee on or within thirty (30)
                                    days following the Effective Date.

                        (2)   Change of Control in a Transaction With a Public
                              Company. In the event a Change of Control occurs
                              between Employer and a company whose common stock
                              is publicly traded on the domestic national
                              exchange, the NASDAQ national market, or their
                              respective successors and equivalents (a "Public
                              Company"), then

                              (a)   all of Employee's stock options (vested and
                                    unvested) granted by Employer prior to the
                                    Effective Date shall at the sole election of
                                    Employee either (1) be (a) deemed to be
                                    fully exercisable upon the Effective Date
                                    and (b)

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                                    cashed out at the transaction value as
                                    calculated as of the Effective Date less the
                                    exercise price of such stock options and
                                    paid by the Surviving Entity to Employee on
                                    or within thirty (30) days following the
                                    Effective Date or (2) be converted into
                                    stock options of the Surviving Entity, if
                                    applicable, on substantially equivalent
                                    economic terms and including the same
                                    provisions regarding accelerated vesting in
                                    connection with the termination of
                                    employment following a Change of Control
                                    (the "Replacement Options"). If Replacement
                                    Options are granted, they shall continue to
                                    vest at the same rate as under the
                                    applicable equity incentive plan of Employer
                                    and corresponding option agreement in effect
                                    prior to the Change of Control.

                              (b)   all restrictions on transferability of
                                    restricted stock held by the Employee on the
                                    Effective Date shall be deemed to have
                                    terminated immediately prior to the
                                    Effective Date, unless the Employee is
                                    provided with stock of the Surviving Company
                                    with transfer restrictions on substantially
                                    equivalent economic terms; and

                              (c)   all of the stock appreciation rights (vested
                                    and unvested) granted by Employer prior to
                                    the Effective Date shall at the sole
                                    election of Employee either (1) be (a)
                                    deemed to be fully exercisable upon the
                                    Effective Date and (b) cashed out at the
                                    transaction value as calculated as of the
                                    Effective Date and paid by the Surviving
                                    Entity to Employee on or within thirty (30)
                                    days following the Effective Date or (2) be
                                    converted into stock appreciation rights of
                                    the Surviving Entity, if applicable, on
                                    substantially equivalent economic terms and
                                    including the same provisions regarding
                                    accelerated vesting in connection with the
                                    termination of employment following a Change
                                    of Control (the "Replacement SARs"). If
                                    Replacement SARs are granted, they shall
                                    continue to vest at the same rate as under
                                    the applicable equity incentive plan of
                                    Employer and corresponding stock
                                    appreciation right agreement in effect prior
                                    to the Change of Control.

      (c)   This Section 5 shall supercede any other change of control agreement
            or arrangement previously entered into by and between Employer and
            Employee.

6.    Employee agrees that the current noncompetition agreement between Employee
      and Employer will remain in effect until three (3) years after the
      termination of the Position Term.

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7.    Employer denies that it is liable to Employee for any reason whatsoever,
      and the entry into this Agreement shall not constitute any admission or
      evidence of unlawful discrimination or improper conduct, and should not be
      construed as constituting any admission of fault, wrongdoing, or
      liability.

8.    Employee releases, forever discharges and covenants not to sue Employer or
      its current or former parent companies, subsidiaries, affiliates,
      predecessors, successors, insurers, directors, officers, employees,
      agents, or assigns, with respect to any and all claims, causes of action,
      suits, debts, sums of money, controversies, agreements, promises, damages,
      and demands whatsoever, including attorneys' fees and court costs, in law
      or equity or before any federal, state or local administrative agency,
      whether known or unknown, suspected or unsuspected, which Employee has,
      had, or may have, based on any event occurring, or alleged to have
      occurred, to the date of this Agreement. This release includes, but is not
      limited to, claims under Title VII of the Civil Rights Act of 1964, as
      amended, the Americans with Disabilities Act, the Rehabilitation Act, the
      Age Discrimination in Employment Act, the Occupational Safety and Health
      Act, the Family and Medical Leave Act, the Employee Retirement Income
      Security Act, federal and state wage and hour laws, the Illinois
      Constitution, any Illinois human rights acts, and any other federal, state
      or local statute, law, regulation, ordinance, or order, and claims arising
      under common law, contract, implied contract, public policy or tort.
      Employee expressly waives his right to any relief of any kind should any
      administrative agency pursue any claim on Employee's behalf.
      Notwithstanding the foregoing release of all claims, it is understood and
      agreed that Employee's claims for unemployment compensation, if any, are
      not released.

9.    Employee expressly waives and relinquishes all rights and benefits
      provided to Employee by any statute or other law which prohibits release
      of unspecified claims and acknowledges that this release is intended to
      include all claims Employee has or may have up to and including the date
      of this Agreement, whether Employee is aware of them or not, and that all
      such claims are released by this Agreement.

10.   Employee agrees as follows:

      (a)   Employee agrees to use reasonable efforts to cooperate with Employer
            in regard to the transition of business matters handled by Employee
            during his employment in the capacity of Executive Vice President,
            Corporate Operations, Chief Financial Officer and Secretary with
            Employer.

      (b)   Employee agrees to cooperate as practicable in regard to any
            litigation brought against Employer arising out of matters involving
            Employee. Employer acknowledges that Employee's obligations to his
            subsequent employer may preclude his active participation in such
            above-described litigation against Employer. Should Employer desire
            Employee's cooperation in litigation, Employer shall contact
            Employee and apprise him of the nature of the litigation, the
            purpose for which Employer desires Employee's cooperation and the
            anticipated time commitment. Employee shall have the right to
            request reimbursement for all reasonable travel-related expenses
            incurred at Employer's request in the performance of his obligations
            under this Section 10(b).

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      (c)   Upon termination of his employment, Employee will return all
            property of Employer within his possession and control to Employer.

11.   Employee will direct all requests for references to Employer's Human
      Resources Department. Employer's Human Resources Department will respond
      to any written requests for references from prospective employers of
      Employee with information as to Employee's dates of employment with
      Employer, job title and pay rate only.

12.   Neither Employer nor Employee shall make statements about the other or
      engage in conduct that could reasonably be expected to adversely affect
      Employee's or Employer's reputation or business, other than as required by
      law.

13.   Upon termination of his employment, Employee agrees that Employee shall
      receive only the rights and benefits set forth in Section 3 above.

14.   This Agreement will not take effect until eight days after Employee signs
      it.

15.   Employee may revoke this Agreement within seven days after signing it and
      render it null and void. If Employee wishes to revoke this Agreement, he
      should notify Anthony Ciro, Assistant Secretary and Vice President, Legal
      Counsel and Operations in writing of Employee's intent to revoke within
      seven days after signing this Agreement.

16.   Employee acknowledges that he has fully read this Agreement, understands
      its terms, has been advised to consult with an attorney prior to signing
      this Agreement, has been given 45 days to consider this release and its
      ramifications, has been given seven days after signing to rescind this
      Agreement, and is entering into this Agreement knowingly and voluntarily.

17.   Employer and Employee agree to amend this Agreement, as reasonably
      necessary, to conform to the new Code Section 409A, which section was
      created by the American Jobs Creation Act of 2004.

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                                                   THIS DOCUMENT IS A RELEASE OF
                                                   ALL CLAIMS READ CAREFULLY
                                                   BEFORE SIGNING

DATED:  December 7, 2004                           /s/ Edward Hamburg
                                                   -----------------------------
                                                   Edward Hamburg

                                                   SPSS INC.

DATED:  December 7, 2004                           /s/ Anthony Ciro
                                                   -----------------------------
                                                   Name: Anthony Ciro
                                                   Its: Assistant Secretary
                                                        Vice President, Legal
                                                        Counsel and Operations

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