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                                                                    EXHIBIT 4.02

                           CBS EMPLOYER SERVICES, INC.

                        INCENTIVE STOCK OPTION AGREEMENT

        CBS EMPLOYER SERVICES, INC., a Texas corporation (the "Company"), hereby
grants this [_____] day of [____________], [_____] (the "Grant Date"), to [Name
of Employee] (the "Employee"), an option to purchase a maximum of ______________
shares of the Company's Class A Common Stock, $0.001 par value per share (the
"Common Stock"), at the price of [$_______] per share, on the following terms
and conditions:

        1. Grant Under 2000 Stock Option/Stock Issuance Plan. (a) This option is
granted pursuant to and is governed by and subject to the Company's 2000 Stock
Option/Stock Issuance Plan (the "Plan"), the terms and conditions of which are
incorporated herein by this reference. Unless the context otherwise requires,
terms used herein shall have the same meaning as in the Plan. Determinations
made pursuant to the Plan in connection with this option shall be governed by
the Plan as it exists on the date of this option agreement ("Agreement").

           (b) The granting of this option shall be subject to receipt by the
Company of the Company's then current or standard form of Non-Disclosure,
Non-Competition and Developments Agreement, executed and delivered by the
Employee.

        2. Grant as Incentive Stock Option, Other Options. This option is
intended to qualify as an incentive stock option ("ISO") within the meaning of
Section 422 of the Internal Revenue Code of 1986 (the "Code"). This option is in
addition to any other options heretofore or hereafter granted to the Employee by
the Company, but a duplicate original of this instrument shall not effect the
grant of another option.

        3. Exercise of Option and Provisions for Termination.

           (a) Vesting Schedule. Except as otherwise provided in this Agreement,
and subject to all other terms and conditions of this Agreement, if the Employee
has continued to be employed by the Company through any applicable date in the
table below, this option may be exercised prior to the tenth anniversary of the
Grant Date (hereinafter the "Expiration Date") in installments for not more than
the number of shares set forth opposite such applicable date:

               December 31, 2000          [ ] shares

               March 31, 2001             [ ] shares

               June 30, 2001              [ ] shares

               September 30, 2001         [ ] shares

               December 31, 2001          [ ] shares

               March 31, 2002             [ ] shares

               June 30, 2002              [ ] shares

               September 30, 2002         [ ] shares

               December 31, 2002          [ ] shares

               March 31, 2003             [ ] shares

               June 30, 2003              [ ] shares


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               September 30, 2003          [ ] shares

               December 31, 2003           [ ] shares

The right of exercise shall be cumulative so that if the option is not exercised
to the maximum extent permissible as of an applicable date, it shall be
exercisable, in whole or in part, with respect to all shares not so purchased at
any time prior to the Expiration Date or the earlier termination of this option.
Notwithstanding any other provision of this Agreement or the Plan, this option
may not be exercised at any time on or after the Expiration Date.

           (b) Method of Exercise. Subject to the terms and conditions set forth
in this Agreement, this option shall be exercised by the Employee's delivery of
written notice of exercise to the Chief Financial Officer of the Company,
specifying the number of shares to be purchased and the purchase price to be
paid therefor and accompanied by payment in full in accordance with Section 4
hereof. Such exercise shall be effective upon receipt by the Chief Financial
Officer of the Company of such written notice together with the required
payment. The Employee may purchase less than the number of shares covered
hereby, provided that no partial exercise of this option may be for any
fractional share or for fewer than 50 whole shares.

           (c) Continuous Employment Required. Except as otherwise provided in
this Section 3, this option may not be exercised unless the Employee, at the
time he or she exercises this option, is, and has been at all times since the
Grant Date, an employee of the Company. For all purposes of this Agreement, (i)
"employee" and "employment" shall be defined in accordance with the provisions
of Treasury Regulation Section 1.421-7(h) under the Code, or any successor
regulations, (ii) employment by a parent or subsidiary corporation of the
Company shall be deemed to be employment by the Company and (iii) if this option
shall be assumed or a new option substituted therefor in a transaction to which
Section 424(a) of the Code applies, employment by such assuming or substituting
corporation (hereinafter a "Successor Corporation") shall be considered for all
purposes of this option to be employment by the Company. As used herein, the
terms "parent" and "subsidiary" mean "parent corporation" and "subsidiary
corporation", respectively, as those terms are defined in Sections 424(e) and
424(f) or successor provisions of the Code.

           (d) Exercise Period Upon Termination of Employment. If the Employee
ceases to be employed by the Company for any reason, then, except as provided in
paragraphs (e) and (f) below, the right to exercise this option shall terminate
on the date which is three (3) months after the date of cessation of employment
(but in no event after the Expiration Date); provided, however, that this option
shall be exercisable only to the extent that the Employee was entitled to
exercise this option on the date of such cessation. Notwithstanding the
foregoing, if, in the judgment of the Company, the Employee, prior to the
Expiration Date, materially violates the non-competition or confidentiality
provisions of any employment contract, confidentiality and nondisclosure
agreement or other agreement between the Employee and the Company, the right to
exercise this option shall terminate immediately upon written notice to the
Employee from the Company describing such violation.

           (e) Exercise Period Upon Death or Disability. If the Employee dies or
becomes disabled (within the meaning of Section 22(e)(3) of the Code) prior to
the Expiration Date while he or she is an employee of the Company, or if the
Employee dies within three (3) months after the date on which the Employee
ceases to be an employee of the Company (other than as the result of a discharge
for "cause" as specified in Paragraph (f) below), this option shall be
exercisable within the period of one (1) year following the date of death or
disability of the Employee (but in no event after the Expiration Date), by the
Employee or by the person to whom this option is transferred by will or the laws
of descent and distribution; provided, however, that this option shall be
exercisable only to the extent that this option was exercisable by the Employee
on the date of his or her death or disability. Except as otherwise indicated by
the context, the term "Employee", as used in this Agreement, shall include the
estate of the Employee, the Employee's personal representative, or any other
person who acquires the right to exercise this option by bequest or inheritance
or otherwise by reason of the death of the Employee or by reason of the
Employee's incapacity.

           (f) Discharge for Cause. If the Employee, prior to the Expiration
Date, is discharged by the Company for "cause" (as defined below), the right to
exercise this option shall terminate immediately upon such discharge. "Cause"
shall mean willful misconduct or willful failure by the Employee to perform his
or her


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employment responsibilities in the best interests of the Company (including,
without limitation, breach by the Employee of any provision of any employment,
nondisclosure, non-competition or other similar agreement between the Employee
and the Company), as determined by the Company, which determination shall be
conclusive. The Employee shall be considered to have been discharged "for cause"
if the Company determines, within thirty (30) days after the Employee's
resignation, that discharge for cause was warranted.

        4. Payment of Purchase Price. Payment of the purchase price for shares
purchased upon exercise of this option shall be made by delivery to the Company
of cash or wire transfer or a check payable to the order of the Company in an
amount equal to the purchase price per share as hereinabove set forth times the
number of shares so purchased (the "exercise price"); or by any other means that
the Board of Directors determines are consistent with the purpose of the Plan
and with applicable laws and regulations.


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        5. Delivery of Shares.

           (a) General. The Company shall, upon payment of the exercise price
for the number of shares purchased and paid for, make prompt delivery of such
shares to the Employee; provided, however, that if any law or regulation
requires the Company to take any action with respect to such shares before the
issuance thereof, then the date of delivery of such shares shall be extended for
the period necessary to complete such action.

           (b) Listing, Registration, Qualification, Etc. This option shall be
subject to the requirement that if, at any time, counsel to the Company shall
determine that the listing, registration or qualification of the shares subject
hereto upon any securities exchange or under any state or federal law, or the
consent or approval of any governmental or regulatory body, or that the
disclosure of non-public information or the satisfaction of any other condition
is necessary as a condition of, or in connection with, the issuance or purchase
of shares hereunder, this option may not be exercised, in whole or in part,
unless such listing, registration, qualification, consent or approval,
disclosure or satisfaction of such other condition shall have been effected or
obtained on terms acceptable to the Board of Directors of the Company. Nothing
herein shall be deemed to require the Company to apply for, effect or obtain
such listing, registration, qualification, or disclosure, or to satisfy such
other condition.

        6. Nontransferability of Option. Except as provided in Paragraph (e) of
Section 3 hereof, this option is personal and no rights granted hereunder may be
transferred, assigned, pledged or hypothecated in any way (whether by operation
of law or otherwise) nor shall any such rights be subject to execution,
attachment or similar process. Upon any attempt to transfer, assign, pledge,
hypothecate or otherwise dispose of this option or of such rights contrary to
the provisions hereof, or upon the levy of any attachment or similar process
upon this option or such rights, this option and such rights shall, at the
election of the Company, become null and void.

        7. No Special Employment Rights. Nothing contained in the Plan or this
Agreement shall be construed or deemed by any person under any circumstances to
obligate the Company to continue the employment of the Employee for any period.

        8. Rights as a Shareholder. The Employee shall have no rights as a
shareholder with respect to any shares which may be purchased by exercise of
this option (including, without limitation, any rights to vote or to receive
dividends or other distributions with respect to such shares) unless and until a
certificate representing such shares is duly issued and delivered to the
Employee. No adjustment shall be made for dividends or other rights for which
the record date is prior to the date such stock certificate is issued.

        9. Adjustment Provisions.

           (a) General. If through, or as a result of, any merger,
consolidation, sale of all or substantially all of the assets of the Company,
reorganization, recapitalization, reclassification, stock dividend, stock split,
reverse stock split or other similar transaction, (i) the outstanding shares of
Common Stock are increased or decreased or are exchanged for a different number
or kind of shares or other securities of the Company, or (ii) additional shares
or new or different shares or other securities of the Company or other non-cash
assets are distributed with respect to such shares of Common Stock or other
securities, the Employee shall, with respect to this option or any unexercised
portion hereof, be entitled to the rights and benefits, and be subject to the
limitations, set forth in Paragraph 14 of the Plan.

           (b) Board Authority to Make Adjustments. Any adjustments under this
Section 9 shall be made by the Board of Directors of the Company, whose
determination as to what adjustments, if any, will be made and the extent
thereof will be final, binding and conclusive. No fractional shares will be
issued with respect to this option on account of any such adjustments.

           (c) Limits on Adjustments. No adjustment shall be made under this
Section 9 which would, for purposes of any applicable provision of the Code,
constitute a modification, extension or renewal of this option or a grant of
additional benefits to the Employee.


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        10. Mergers, Consolidations, Asset Sales, Liquidations, Etc. In the
event of a consolidation or merger or sale of all or substantially all of the
assets of the Company in which outstanding shares of Common Stock are exchanged
for securities, cash or other property of any other corporation or business
entity, or in the event of the liquidation of the Company, prior to the
Expiration Date or other termination of this option, the Employee shall, with
respect to this option or any unexercised portion hereof, be entitled to the
rights and benefits, and be subject to the limitations, set forth in Paragraph
16 of the Plan.

        11. Withholding of Taxes. The Company's obligation to deliver shares
upon the exercise of this option shall be subject to the Employee's satisfaction
of all applicable federal, state and local income and employment tax withholding
requirements as described in Paragraph 23 of the Plan. Without limiting the
generality of the foregoing, if the Company in its discretion determines that it
is obligated to withhold tax with respect to a Disqualifying Disposition (as
defined in Section 12 hereof), the Employee agrees that the Company may withhold
from the Employee's wages the appropriate amount of federal, state and local
withholding taxes attributable to such Disqualifying Disposition. If any portion
of this option is treated as a Non-Qualified Option, the Employee agrees that
the Company may withhold from the Employee's wages the appropriate amount of
federal, state and local withholding taxes attributable to the Employee's
exercise of such Non-Qualified Option. At the Company's discretion, the amount
required to be withheld may be withheld in cash from such wages, or otherwise as
may be permitted under the Plan. The Employee further agrees that, if the
Company does not withhold an amount from the Employee's wages sufficient to
satisfy the Company's withholding obligation or if such obligation is not
otherwise satisfied, as determined by the Company, the Employee will reimburse
the Company on demand, in cash, for the amount underwithheld.

        12. Holding Period Requirements for Incentive Stock Option Shares. It is
understood and intended that this option shall qualify as an "incentive stock
option" as defined in Section 422 of the Code (an "ISO"). Accordingly, the
Employee understands that in order to obtain the beneficial tax treatment
accorded an ISO, no sale or other disposition may be made of any shares acquired
upon exercise of the option within one (1) year after the day of the transfer of
such shares to the Employee, nor within two (2) years after the Grant Date. If
the Employee intends to dispose, or does dispose (whether by sale, exchange,
gift, transfer or otherwise), of any such shares within either of said periods,
he or she will notify the Company in writing within ten (10) days after such
disposition (a "Disqualifying Disposition").

        13. Investment Representations, Warranties and Covenants; Legends.

            (a) Representations. The Employee represents, warrants and covenants
that:

                (i) Any shares purchased upon exercise of this option shall be
            acquired for the Employee's account for investment only and not with
            a view to, or for sale in connection with, any distribution of the
            shares in violation of the Securities Act of 1933 (the "Securities
            Act") or any rule or regulation under the Securities Act.

                (ii) The Employee has had such opportunity as he or she has
            deemed adequate to obtain from representatives of the Company such
            information as is necessary to permit the Employee to evaluate the
            merits and risks of his or her investment in the Company.

                (iii) The Employee is able to bear the economic risk of holding
            shares acquired pursuant to the exercise of this option for an
            indefinite period.

                (iv) The Employee understands that (A) the shares acquired
            pursuant to the exercise of this option will not be registered under
            the Securities Act and are "restricted securities" within the
            meaning of Rule 144 under the Securities Act; (B) such shares cannot
            be sold, transferred or otherwise disposed of unless they are
            subsequently registered under the Securities Act or an exemption
            from registration is then available; (C) in any event, an exemption
            from registration under Rule 144 or otherwise under the Securities
            Act may not be available for at least one year and even then will
            not be available unless a public market then exists for the Common
            Stock, adequate information concerning the Company is then available
            to the public and other terms and


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            conditions of Rule 144 are complied with; and (D) there is now no
            registration statement on file with the Securities and Exchange
            Commission with respect to any stock of the Company and the Company
            has no obligation or current intention to register any shares
            acquired pursuant to the exercise of this option under the
            Securities Act.

                (v) The Employee agrees that, if the Company offers for the
            first time any of its Common Stock for sale pursuant to a
            registration statement under the Securities Act, the Employee will
            not, without the prior written consent of the Company, publicly
            offer, sell, contract to sell or otherwise dispose of, directly or
            indirectly, any shares purchased upon exercise of this option for a
            period of ninety (90) days, or such longer period as the Company may
            reasonably require, after the effective date of such registration
            statement.

                (vi) The Employee's principal residence is at the address set
            forth below on the signature page. The Employee shall promptly
            notify the Company of any change in the Employee's principal
            residence.

By making payment upon any exercise of this option, in whole or in part, the
Employee shall be deemed to have reaffirmed, as of the date of such payment, the
representations made in this Section 13.

            (b) Legends on Stock Certificates. All stock certificates
representing shares of Common Stock issued to the Employee upon exercise of this
option shall have affixed thereto legends substantially in the following forms,
in addition to any other legends required by applicable state law:

            "The shares of stock represented by this certificate have not been
            registered under the Securities Act of 1933 and may not be
            transferred, sold or otherwise disposed of in the absence of an
            effective registration statement with respect to the shares
            evidenced by this certificate, filed and made effective under the
            Securities Act of 1933, or an opinion of counsel satisfactory to the
            Company to the effect that registration under such Act is not
            required."

            "The shares of stock represented by this certificate are subject to
            certain restrictions on transfer contained in an Option Agreement
            and in a Security Holders Agreement, copies of which will be
            furnished upon request by the issuer."

        14. Execution of the Certain Agreements as Condition of Exercise. The
shareholders of the Company have entered into a certain agreement dated April 1,
1999, imposing certain restrictions on the outstanding shares of Common Stock of
the Company and regulating certain aspects of the relationships among the
shareholders and between the Company and each of the shareholders (the "Security
Holders' Agreement"). As a condition to any exercise of this option, the
Employee (a) shall become a party to the Security Holders' Agreement, as amended
(or any substitute agreement among the shareholders as then in effect, and shall
execute such agreement as a shareholder), and (b) shall execute and deliver a
redemption agreement (the "Redemption Agreement") pursuant to which the Company
shall have the right, but not the obligation, exercisable by the Company
following the Employee's death, disability or termination (for any reason) of
employment with the Company, to purchase any shares of Common Stock issued to
the Employee upon exercise of this Option, such purchase to be made at the fair
market value of the Company's Common Stock as at the date of the Employee's
death, disability or termination. Promptly upon receipt by the Chief Financial
Officer of the Company of the written notice and payment provided for in Section
3(b) hereof, the Chief Financial Officer shall cause the Employee to be provided
with copies of the latest Security Holders' Agreement (or substitute agreement)
and the Redemption Agreement, and shall arrange for the Employee's execution of
an original or original counterpart of each. Upon the Employee's execution of
such agreements, subject to all other terms and conditions of this Agreement,
the Employee's option exercise shall be effective. If the Employee refuses to
execute such agreements, the Chief Financial Officer shall cause the aforesaid
payment to be returned to the Employee, and the Employee's attempted option
exercise shall be null and void and without effect.


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        15. Miscellaneous.

            (a) Except as otherwise expressly provided herein, this Agreement
may not be amended or otherwise modified unless evidenced in writing and signed
by the Company and the Employee.

            (b) All notices under this Agreement shall be delivered by hand,
sent by commercial overnight courier service or sent by registered or certified
mail, return receipt requested, and first-class postage prepaid, to the parties
at their respective addresses set forth beneath their names below or at such
other address as may be designated in a notice by either party to the other.
Notwithstanding the foregoing, any notice sent to such an address in a country
other than that from which the notice is sent may be sent by telefax, telegram
or commercial air courier.

            (c) Any reference in this Agreement to a Section of the Code shall
refer to that Section as it reads as of the date of this Agreement and as it may
be amended from time to time, and to any successor provision.

            (d) Each provision of this Agreement shall be considered separable.
The invalidity or unenforceability of any provision shall not affect the other
provisions, and this Agreement shall be construed in all respects as if such
invalid or unenforceable provision were omitted.

            (e) Sections 12, 13, 14 and 15 hereof shall survive any termination
of this Agreement.

            (f) This Agreement shall be governed by and construed in accordance
with the laws of the State of Texas.

            (g) The failure of the Company or the Employee to insist upon strict
performance of any provision hereunder, irrespective of the length of time for
which such failure continues, shall not be deemed a waiver of such party's right
to demand strict performance at any time in the future. No consent or waiver,
express or implied, to or of any breach or default in the performance of any
obligation or provision hereunder shall constitute a consent or waiver to or of
any other breach or default in the performance of the same or any other
obligation hereunder.

            (h) Except for the right of any party to apply to a court of
competent jurisdiction for a temporary restraining order, preliminary
injunction, or other equitable relief to preserve the status quo or prevent
irreparable harm pending the selection and confirmation of an arbitrator, any
controversy or claim arising out of or relating to this Agreement, including
without limitation claims under the Americans with Disabilities Act, the Age
Discrimination in Employment Act of 1967, as amended, Title VII of the Civil
Rights Act of 1964 as amended, or any other applicable state or federal
statutory or common law; shall be resolved by arbitration in Fort Worth, Texas,
in accordance with the governing rules of the American Arbitration Association
(the "AAA"). A demand for arbitration shall be filed with the AAA during the
term, or within six months after termination or expiration, of this Agreement.
The arbitrator shall have the authority to permit discovery, to the extent
deemed appropriate by the arbitrator, upon the request of a party and to grant
any type of injunctive relief as well as award damages; provided, however, the
arbitrator shall have no authority to award multiple or punitive damages. The
costs of the arbitration proceeding, including the fee of the arbitrator, shall
be borne equally by the parties. Each party shall bear the costs of its own
counsel. Judgment upon the award entered may be enforced by any court of
competent jurisdiction.

Date of Grant: [____________]

                                        CBS EMPLOYER SERVICES, INC.


                                        By: ___________________________________
                                        Title: ________________________________
                                        Address:_______________________________


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                                           ------------------------------------
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                              EMPLOYEE'S ACCEPTANCE

        The undersigned hereby accepts the foregoing option and agrees to the
terms and conditions of this Agreement. The undersigned hereby acknowledges
receipt of a copy of the Company's 2000 Stock Option/Stock Issuance Plan.

                                           [Name of Employee]

                                           ------------------------------------
                                           Signature

                                           Address:

                                           ------------------------------------
                                           ------------------------------------

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