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                                                                   EXHIBIT 10.46

                                    SPSS INC.
                     QUALIFIED EMPLOYEE STOCK PURCHASE PLAN
                        EFFECTIVE AS OF SEPTEMBER 1, 2000

                             SECTION 1. INTRODUCTION

         The SPSS Inc. Employee Stock Purchase Plan (the "Plan") is designed to
provide employees of SPSS Inc. ("Company") and its wholly owned subsidiaries the
opportunity to acquire shares of common stock ("Stock") of the Company on a
quarterly basis through payroll deductions at a price equal to 85% of the then
market price of the Stock. It is the intention of the Company to have the Plan
qualify as an "employee stock purchase plan" under Section 423 of the Internal
Revenue Code of 1986, as amended (the "Code"). The provisions of the Plan shall,
accordingly, be construed so as to extend and limit participation in a manner
consistent with the requirements of that section of the Code.

                          SECTION 2. ELIGIBLE EMPLOYEES

         All hourly and salaried employees are eligible to participate in the
Plan. To participate in any particular quarter, employees must be employed prior
to the end of the enrollment period for that quarter.

          SECTION 3. ELECTION TO PURCHASE STOCK AND PAYROLL DEDUCTIONS

         3.1 As of the first day of each calendar quarter, each salaried
employee may elect to have an amount deducted from his pay during the calendar
quarter equal to one, two, three, four, five, six, seven, eight, nine or ten
percent of his or her salary, bonus and commission paid during such calendar
quarter. Each eligible employee who elects to participate in the Plan (a
"Participant") shall deliver to the Company during the enrollment period a
written payroll deduction authorization on a form acceptable to the Plan
Administrator (as defined hereinafter),

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or if there is no Plan Administrator, the Administrative Committee (as defined
hereinafter), (i) giving notice of the Participant's election to have amounts
deducted from such Participant's pay which may be used by the Participant to
purchase shares of Stock under the Plan and (ii) designating an amount to be
deducted from his pay during the time the Participant is enrolled in the Plan,
which designation shall equal one, two, three, four, five, six, seven, eight,
nine or ten percent of the Participant's salary, bonus and commission. An amount
determined by multiplying the selected percentage by the Participant's salary,
bonus and commission shall be deducted from each paycheck during the calendar
quarter, so that the total deductions during the calendar quarter will equal the
withholding amount elected.

         3.2 There will be an enrollment period established by the
Administrative Committee during which eligible employees may elect to
participate in the Plan and designate the percentage of payroll deductions.
Elections may not be made or modified after the end of the enrollment period
except as provided in Sections 3.3 and 5, or as otherwise may be required by
law.

         3.3 Any eligible employee may join the Plan as of the first day of any
calendar quarter. Any Participant employee may withdraw from the Plan at any
time at any time prior to the end of a calendar quarter and receive a refund of
money deducted from the employee's salary, bonus and commission and not used for
the purchase of stock. A Participant withdrawing from the Plan may not rejoin
the Plan until the beginning of the next calendar quarter.

         3.4 No interest will be paid or accrued on any money withheld through
payroll deductions under this Plan.

         3.5 A stock purchase account shall be established for each Participant
(an "Account"), to which all payroll deductions made for that employee will be
credited. Amounts credited to


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Accounts of employees of the Company or the subsidiaries will be under the
control of the Company, may be mixed or commingled with any other funds of the
Company, may be maintained or controlled as a single fund or account, and may be
used for any corporate purpose. No interest will be paid or credited to any
Participant or any Account under the Plan.

         3.6 In the event that any law or regulation, in the opinion of counsel
for the Company, may prohibit the handling or use of all or any part of the
funds in the manner contemplated by the Plan, the Company may deal with such
funds in any lawful manner it may deem advisable, including (without limitation)
the deposit of any such funds in individual bank accounts opened for employees.

                           SECTION 4. STOCK PURCHASES

         4.1 At the beginning of each calendar quarter, a Participant shall be
granted an option to purchase a number of whole shares of Stock determined by
dividing the amount to be withheld for participation in the Plan and applied to
such calendar quarter by the option price per share for such calendar quarter.
The option price per share for each calendar quarter shall equal 85% of the
lower of (i) the closing market price for the Stock on the first trading day
after the end of the previous calendar quarter or (ii) the closing market price
for the Stock on the last trading day of such calendar quarter. Unless a
Participant withdraws from the Plan pursuant to Section 3.3, at the end of each
calendar quarter, funds deducted from a Participant's paycheck during such
quarter will be used to exercise the option.

         4.2 No fractional shares will be purchased. Any funds remaining after
purchasing the maximum number of whole shares which the Participant may purchase
based on the Participant's


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payroll deductions will be carried over the following calendar quarter if the
Participant continues to participate in the Plan or refunded if the Participant
withdraws from the Plan.

         4.3 The Company will issue to each Participant in the Participant's
name, the number of whole shares of Stock purchased for the Participant, as soon
as practicable following the date of purchase. The Participant shall be entitled
to all rights as a holder of Stock with respect to any shares issued to him or
her, including the right to vote such shares. The Participant shall not have the
rights of a stockholder with respect to shares of Stock purchased under this
Plan until such shares have actually been issued to the Participant.

         4.4 If the Company is required to obtain any governmental authority to
issue such shares of Stock, the Company will take all reasonable steps to obtain
that authority. The inability of the Company to obtain any governmental
authority considered necessary for the lawful issuance of such shares shall
relieve the Company from liability to any Participant in the Plan except to
return the amount of the balance in the Participant's Account, without interest.


         4.5 Shares issued under the Plan may be authorized and unissued shares
or shares reacquired by the Company and held as treasury shares.

         4.6 Each employee shall be responsible for the federal and state income
and social security taxes due on the 15% market discount, and the Company will
withhold from the employee's paycheck immediately following each quarterly
purchase the appropriate amount of tax according to the withholding rules then
in effect.

         4.7 Any provision of the Plan to the contrary notwithstanding, no
Participant shall be granted an option: (i) if immediately after the grant the
Participant would own shares, and/or hold outstanding options to purchase stock,
possessing 5% or more of the total combined voting


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power or value of all classes of shares of the Company or any subsidiary of the
Company; or (ii) which permits his rights to purchase shares under all employee
stock purchase plans of the Company and its subsidiaries (as defined under Code
Section 423) to accrue at a rate which exceeds $25,000 of the fair market value
of the shares (determined at the time such option is granted) for each calendar
year in which such stock option is outstanding at any time.

         4.8 The maximum number of shares which shall be made available under
the Plan shall be 100,000.

                     SECTION 5. CHANGE IN EMPLOYMENT STATUS

         5.1 Any employee whose employment terminates for any reason, other than
for cause, may elect to withdraw the aggregate amount deducted from his or her
paycheck then in the Company's possession, without interest, or may leave such
amount with the Company to fund a stock purchase at the end of the calendar
quarter. Any employee terminated for cause shall receive a refund of the amount
deducted from his or her paycheck then in the Company's possession, without
interest.

         5.2 If a participating employee dies, the amount deducted from his or
her paycheck then in the Company's possession shall be refunded to the legal
representative of the Participant, without interest.

                                SECTION 6. OTHER

         6.1 The stock purchase rights provided in the Plan shall be
nonassignable. Any attempted voluntary assignment or transfer shall be void.

         6.2 The Plan shall be administered by an Administrative Committee (the
"Administrative Committee"), the members of which shall be designated by the
Board. The


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Administrative Committee shall have the sole and absolute power and authority to
construe and interpret the Plan and adopt from time to time such rules and
regulations as it deems necessary to carry out the Plan. Determinations,
interpretations or other actions made or taken by the Administrative Committee
pursuant to the provisions of the Plan shall be final, binding and conclusive
for all purposes and upon all Participants. The Administrative Committee may
appoint a Plan Administrator (the "Plan Administrator"), who shall have the
responsibility and authority to carry out the Plan consistently with the Plan
and any rules and regulations established by the Administrative Committee.

         6.3 The Board shall have the right to terminate, suspend or modify the
Plan in any way at any time, without notice; provided, however, that, except as
otherwise explicitly set forth herein, no suspension, termination, amendment or
modification may be made which would impair the rights of a Participant under
the Plan with respect to any outstanding rights to purchase Stock without the
consent of such Participant, unless such suspension, termination, amendment or
modification is necessary to comply with any applicable law.

                        SECTION 7. NO RIGHT TO EMPLOYMENT

         Neither the adoption of the Plan nor the purchase of Stock under the
Plan shall confer upon any employee of the Company or any subsidiary corporation
any right to continued employment nor shall it interfere with the right of the
Company and its subsidiary corporations to terminate the employment of any of
their employees at any time, with or without cause.


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                            SECTION 8. GOVERNING LAW

         The Plan and all determinations made and actions taken pursuant to the
Plan shall be construed and enforced in accordance with the laws of the State of
Illinois, without regard to its conflicts of law principles. The provisions of
the Plan shall be interpreted in a manner necessary to sustain its legality and
enforceability. The unenforceability of any provision of the Plan in a specific
situation shall not affect the enforceability of that provision in another
situation or the other provisions of the Plan.

                               SECTION 9. DISPUTES

         All disputes arising out of the interpretation or application of the
Plan shall be decided by the Administrative Committee. In the event of a dispute
with a Participant, the Administrative Committee shall provide that Participant
with a written determination within 30 days of its decision with respect to the
dispute.

                        SECTION 10. CERTAIN PARTICIPANTS

         With respect to persons subject to Section 16 of the Securities
Exchange Act of 1934 ("1934 Act"), transactions under this Plan are intended to
comply with all applicable conditions of Rule 16b-3 or any replacement rules or
regulations under the 1934 Act and, with respect to such persons, the
Administrative Committee and the Plan Administrator may take such additional
actions and/or require such additional or different agreements of such persons
(with such persons' consent) as necessary or appropriate (on the advice of
counsel to the Company) to ensure that transactions involving such persons
hereunder are exempt under Section 16 of the 1934 Act. To the extent any
provision of the Plan or action by the Administrative Committee or the Plan
Administrator fails to comply with all applicable conditions of Rule 16b-3 or
any replacement


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rules or regulations under the 1934 Act, it shall be deemed null and void, to
the extent permitted by law and deemed advisable by the Administrative
Committee.

       SECTION 11. LIMITS ON THE NUMBER OF SECURITIES WHICH MAY BE ISSUED.

         With respect to persons subject to Section 16 of the 1934 Act, such
individuals may purchase shares of Stock with amounts deducted from their
bonuses as well as their base salary, only so long as the maximum number of
securities issuable to such individuals under this Plan shall not increase by
more than ten percent the number of shares of Stock otherwise purchasable under
the Plan.

               SECTION 12. ADJUSTMENTS ON CHANGE IN CAPITALIZATION

         The Board may make or provide for such adjustments in the numbers of
shares of Stock covered by outstanding options granted hereunder, in the prices
per share applicable to such options, and in the kind of shares covered thereby,
as the Board may determine is equitably required to prevent dilution or
enlargement of the rights of Participants that otherwise would result from (a)
any stock dividend, stock split, combination of shares, recapitalization, or
other change in the capital structure of the Company, (b) any merger,
consolidation, spin-off, split-off, spin-out, split-up, reorganization, partial
or complete liquidation, or other distribution of assets or issuance of rights
or warrants to purchase securities, or (c) any other corporate transaction or
event having an effect similar to any of the foregoing; provided, further,
however, that any adjustment which by reason of this Section 12 is not required
to be made currently will be carried forward and taken into account in any
subsequent adjustment. In the event of any such trans action or event, the Board
may provide in substitution for any or all outstanding awards under this Plan
such alternative consideration as it may determine to be equitable in the
circumstances and may require in connection therewith the surrender of all
awards so replaced. The Board may also make or provide for such adjustments in
the numbers of shares specified in Section 4.8 as the Board may determine is
appropriate to reflect any transaction or event described in this Section 12.


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