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                                                                   Exhibit 99.1


                               WIND RIVER SYSTEMS

                          EMPLOYEE STOCK PURCHASE PLAN

                      Adjusted for Stock Split May 24, 1996
                     Adjusted for Stock Split March 10, 1997
                    Adjusted for Stock Split February 4, 1999
                             Amended April 22, 1999
                     Approved by Stockholders June 24, 1999
                            Amended January 14, 2000
                     Approved by Stockholders July 26, 2000


         1.       PURPOSE.

                  (a) The purpose of the Employee Stock Purchase Plan (the
"Plan") is to provide a means by which employees of Wind River Systems, Inc., a
Delaware corporation (the "Company"), and its Affiliates, as defined in
subparagraph 1(b), which are designated as provided in subparagraph 2(b), may be
given an opportunity to purchase stock of the Company.

                  (b) The word "Affiliate" as used in the Plan means any parent
corporation or subsidiary corporation of the Company, as those terms are defined
in Sections 424(e) and (f), respectively, of the Internal Revenue Code of 1986,
as amended (the "Code").

                  (c) The Company, by means of the Plan, seeks to retain the
services of its employees, to secure and retain the services of new employees,
and to provide incentives for such persons to exert maximum efforts for the
success of the Company.

                  (d) The Company intends that the rights to purchase stock of
the Company granted under the Plan be considered options issued under an
"employee stock purchase plan" as that term is defined in Section 423(b) of the
Code.

         2.       ADMINISTRATION.

                  (a) The Plan shall be administered by the Board of Directors
(the "Board") of the Company unless and until the Board delegates administration
to a Committee, as provided in subparagraph 2(c). Whether or not the Board has
delegated administration, the Board shall have the final power to determine all
questions of policy and expediency that may arise in the administration of the
Plan.

                  (b) The Board shall have the power, subject to, and within
the limitations of, the express provisions of the Plan:


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                           (i)   To determine when and how rights to purchase
stock of the Company shall be granted and the provisions of each offering of
such rights (which need not be identical).

                           (ii)  To designate from time to time which
Affiliates of the Company shall be eligible to participate in the Plan.

                           (iii) To construe and interpret the Plan and
rights granted under it, and to establish, amend and revoke rules and
regulations for its administration. The Board, in the exercise of this power,
may correct any defect, omission or inconsistency in the Plan, in a manner
and to the extent it shall deem necessary or expedient to make the Plan fully
effective.

                           (iv)  To amend the Plan as provided in paragraph 13.

                           (v)   Generally, to exercise such powers and to
perform such acts as the Board deems necessary or expedient to promote the
best interests of the Company.

                  (c) The Board may delegate administration of the Plan to a
Committee composed of not fewer than two (2) members of the Board (the
"Committee"). If administration is delegated to a Committee, the Committee shall
have, in connection with the administration of the Plan, the powers theretofore
possessed by the Board, subject, however, to such resolutions, not inconsistent
with the provisions of the Plan, as may be adopted from time to time by the
Board. The Board may abolish the Committee at any time and revest in the Board
the administration of the Plan.

         3.       SHARES SUBJECT TO THE PLAN.

                  (a) Subject to the provisions of paragraph 12 relating to
adjustments upon changes in stock, the stock that may be sold pursuant to rights
granted under the Plan shall not exceed in the aggregate three million
(3,000,000) shares of the Company's common stock (the "Common Stock"). If any
right granted under the Plan shall for any reason terminate without having been
exercised, the Common Stock not purchased under such right shall again become
available for the Plan.

                  (b) The stock subject to the Plan may be unissued shares or
reacquired shares, bought on the market or otherwise.

         4.       GRANT OF RIGHTS; OFFERING.

                  The Board or the Committee may from time to time grant or
provide for the grant of rights to purchase Common Stock of the Company under
the Plan to eligible employees (an "Offering") on a date or dates (the "Offering
Date(s)") selected by the Board or the Committee. Each Offering shall be in such
form and shall contain such terms and conditions as the Board or the Committee
shall deem appropriate. If an employee has more than one right outstanding under
the Plan, unless he or she otherwise indicates in agreements or notices
delivered hereunder: (1) each agreement or notice delivered by that employee
will be deemed to apply to all of his or her rights under the Plan, and (2) a
right with a lower exercise price (or an earlier-


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granted right, if two rights have identical exercise prices), will be exercised
to the fullest possible extent before a right with a higher exercise price (or a
later-granted right, if two rights have identical exercise prices) will be
exercised. The provisions of separate Offerings need not be identical, but each
Offering shall include (through incorporation of the provisions of this Plan by
reference in the Offering or otherwise) the substance of the provisions
contained in paragraphs 5 through 8, inclusive.

         5.       ELIGIBILITY.

                  (a) Rights may be granted only to employees of the Company or,
as the Board or the Committee may designate as provided in subparagraph 2(b), to
employees of any Affiliate of the Company. Except as provided in subparagraph
5(b), an employee of the Company or any Affiliate shall not be eligible to be
granted rights under the Plan, unless, on the Offering Date, such employee has
been in the employ of the Company or any Affiliate for such continuous period
preceding such grant as the Board or the Committee may require, but in no event
shall the required period of continuous employment be equal to or greater than
two (2) years. In addition, unless otherwise determined by the Board or the
Committee and set forth in the terms of the applicable Offering, no employee of
the Company or any Affiliate shall be eligible to be granted rights under the
Plan, unless, on the Offering Date, such employee's customary employment with
the Company or such Affiliate is at least twenty (20) hours per week and at
least five (5) months per calendar year.

                  (b) The Board or the Committee may provide that, each person
who, during the course of an Offering, first becomes an eligible employee of the
Company or designated Affiliate will, on a date or dates specified in the
Offering which coincides with the day on which such person becomes an eligible
employee or occurs thereafter, receive a right under that Offering, which right
shall thereafter be deemed to be a part of that Offering. Such right shall have
the same characteristics as any rights originally granted under that Offering,
as described herein, except that:

                           (i)   the date on which such right is granted
shall be the "Offering Date" of such right for all purposes, including
determination of the exercise price of such right;

                           (ii)  the Purchase Period (as defined below) for
such right shall begin on its Offering Date and end coincident with the end
of such Offering; and

                           (iii) the Board or the Committee may provide that
if such person first becomes an eligible employee within a specified period
of time before the end of the Purchase Period (as defined below) for such
Offering, he or she will not receive any right under that Offering.

                  (c) No employee shall be eligible for the grant of any rights
under the Plan if, immediately after any such rights are granted, such employee
owns stock possessing five percent (5%) or more of the total combined voting
power or value of all classes of stock of the Company or of any Affiliate. For
purposes of this subparagraph 5(c), the rules of Section 424(d) of the Code
shall apply in determining the stock ownership of any employee, and stock which
such


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employee may purchase under all outstanding rights and options shall be
treated as stock owned by such employee.

                  (d) An eligible employee may be granted rights under the Plan
only if such rights, together with any other rights granted under "employee
stock purchase plans" of the Company and any Affiliates, as specified by Section
423(b)(8) of the Code, do not permit such employee's rights to purchase stock of
the Company or any Affiliate to accrue at a rate which exceeds twenty-five
thousand dollars ($25,000) of fair market value of such stock (determined at the
time such rights are granted) for each calendar year in which such rights are
outstanding at any time.

                  (e) Officers of the Company and any designated Affiliate shall
be eligible to participate in Offerings under the Plan, provided, however, that
the Board may provide in an Offering that certain employees who are highly
compensated employees within the meaning of Section 423(b)(4)(D) of the Code
shall not be eligible to participate.

         6.       RIGHTS; PURCHASE PRICE.

                  (a) On each Offering Date, each eligible employee, pursuant to
an Offering made under the Plan, shall be granted the right to purchase up to
the number of shares of Common Stock of the Company purchasable with a
percentage designated by the Board or the Committee not exceeding fifteen
percent (15%) of such employee's Earnings (as defined in Section 7(a)) during
the period which begins on the Offering Date (or such later date as the Board or
the Committee determines for a particular Offering) and ends on the date stated
in the Offering, which date shall be no more than twenty-seven (27) months after
the Offering Date (the "Purchase Period"). In connection with each Offering made
under this Plan, the Board or the Committee shall specify a maximum number of
shares which may be purchased by any employee as well as a maximum aggregate
number of shares which may be purchased by all eligible employees pursuant to
such Offering. In addition, in connection with each Offering which contains more
than one Exercise Date (as defined in the Offering), the Board or the Committee
may specify a maximum aggregate number of shares which may be purchased by all
eligible employees on any given Exercise Date under the Offering. If the
aggregate purchase of shares upon exercise of rights granted under the Offering
would exceed any such maximum aggregate number, the Board or the Committee shall
make a pro rata allocation of the shares available in as nearly a uniform manner
as shall be practicable and as it shall deem to be equitable.

                  (b) The purchase price of stock acquired pursuant to rights
granted under the Plan shall be not less than the lesser of:

                         (i)  an amount equal to eighty-five percent (85%) of
the fair market value of the stock on the Offering Date; or

                         (ii) an amount equal to eighty-five percent (85%) of
the fair market value of the stock on the Exercise Date.


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        7.       PARTICIPATION; WITHDRAWAL; TERMINATION.

                  (a) An eligible employee may become a participant in an
Offering by delivering a participation agreement to the Company within the time
specified in the Offering, in such form as the Company provides. Each such
agreement shall authorize payroll deductions of up to the maximum percentage
specified by the Board or the Committee of such employee's Earnings during the
Purchase Period. "Earnings" is defined as the total compensation paid to an
employee, including all salary, wages (including amounts elected to be deferred
by the employee, that would otherwise have been paid, under any cash or deferred
arrangement established by the Company), overtime pay, commissions, bonuses, and
other remuneration paid directly to the employee, but excluding profit sharing,
the cost of employee benefits paid for by the Company, education or tuition
reimbursements, imputed income arising under any Company group insurance or
benefit program, traveling expenses, business and moving expense reimbursements,
income received in connection with stock options, contributions made by the
Company under any employee benefit plan, and similar items of compensation. The
payroll deductions made for each participant shall be credited to an account for
such participant under the Plan and shall be deposited with the general funds of
the Company. A participant may reduce (including to zero), increase or begin
such payroll deductions after the beginning of any Purchase Period only as
provided for in the Offering. A participant may make additional payments into
his or her account only if specifically provided for in the Offering and only if
the participant has not had the maximum amount withheld during the Purchase
Period.

                  (b) At any time during a Purchase Period a participant may
terminate his or her payroll deductions under the Plan and withdraw from the
Offering by delivering to the Company a notice of withdrawal in such form as the
Company provides. Such withdrawal may be elected at any time prior to the end of
the Purchase Period except as provided by the Board or the Committee in the
Offering. Upon such withdrawal from the Offering by a participant, the Company
shall distribute to such participant all of his or her accumulated payroll
deductions (reduced to the extent, if any, such deductions have been used to
acquire stock for the participant) under the Offering, without interest, and
such participant's interest in that Offering shall be automatically terminated.
A participant's withdrawal from an Offering will have no effect upon such
participant's eligibility to participate in any other Offerings under the Plan,
but such participant will be required to deliver a new participation agreement
in order to participate in subsequent Offerings under the Plan.

                  (c) Rights granted pursuant to any Offering under the Plan
shall terminate immediately upon cessation of any participating employee's
employment with the Company and any designated Affiliate, for any reason, and
the Company shall distribute to such terminated employee all of his or her
accumulated payroll deductions (reduced to the extent, if any, such deductions
have been used to acquire stock for the terminated employee), under the
Offering, without interest.

                  (d) Rights granted under the Plan shall not be
transferable, and shall be exercisable only by the person to whom such rights
are granted.


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         8.       EXERCISE.

                  (a) On each exercise date, as defined in the relevant Offering
(an "Exercise Date"), each participant's accumulated payroll deductions and
other additional payments specifically provided for in the Offering (without any
increase for interest) will be applied to the purchase of whole shares of stock
of the Company, up to the maximum number of shares permitted pursuant to the
terms of the Plan and the applicable Offering, at the purchase price specified
in the Offering. No fractional shares shall be issued upon the exercise of
rights granted under the Plan. The amount, if any, of accumulated payroll
deductions remaining in each participant's account after the purchase of shares
which is less than the amount required to purchase one share of stock on the
final Exercise Date of an Offering shall be held in each such participant's
account for the purchase of shares under the next Offering under the Plan,
unless such participant withdraws from such next Offering, as provided in
subparagraph 7(b), or is no longer eligible to be granted rights under the Plan,
as provided in paragraph 5, in which case such amount shall be distributed to
the participant after said final Exercise Date, without interest. The amount, if
any, of accumulated payroll deductions remaining in any participant's account
after the purchase of shares which is equal to the amount required to purchase
whole shares of stock on the final Exercise Date of an Offering shall be
distributed in full to the participant after such Exercise Date, without
interest.

                  (b) No rights granted under the Plan may be exercised to any
extent unless the Plan (including rights granted thereunder) is covered by an
effective registration statement pursuant to the Securities Act of 1933, as
amended (the "Securities Act"). If on an Exercise Date of any Offering hereunder
the Plan is not so registered, no rights granted under the Plan or any Offering
shall be exercised on said Exercise Date and the Exercise Date shall be delayed
until the Plan is subject to such an effective registration statement, except
that the Exercise Date shall not be delayed more than two (2) months and the
Exercise Date shall in no event be more than twenty-seven (27) months from the
Offering Date. If on the Exercise Date of any Offering hereunder, as delayed to
the maximum extent permissible, the Plan is not registered, no rights granted
under the Plan or any Offering shall be exercised and all payroll deductions
accumulated during the purchase period (reduced to the extent, if any, such
deductions have been used to acquire stock) shall be distributed to the
participants, without interest.

         9.       COVENANTS OF THE COMPANY.

                  (a) During the terms of the rights granted under the Plan, the
Company shall keep available at all times the number of shares of stock required
to satisfy such rights.

                  (b) The Company shall seek to obtain from each regulatory
commission or agency having jurisdiction over the Plan such authority as may
be required to issue and sell shares of stock upon exercise of the rights
granted under the Plan. If, after reasonable efforts, the Company is unable
to obtain from any such regulatory commission or agency the authority which
counsel for the Company deems necessary for the lawful issuance and sale of
stock under the Plan, the Company shall be relieved from any liability for
failure to issue and sell stock upon exercise of such rights unless and until
such authority is obtained.


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         10.      USE OF PROCEEDS FROM STOCK.

                  Proceeds from the sale of stock pursuant to rights granted
under the Plan shall constitute general funds of the Company.

         11.      RIGHTS AS A STOCKHOLDER.

                  A participant shall not be deemed to be the holder of, or to
have any of the rights of a holder with respect to, any shares subject to rights
granted under the Plan unless and until the participant's shareholdings acquired
upon exercise of rights under the Plan are recorded in the books of the Company.

         12.      ADJUSTMENTS UPON CHANGES IN STOCK.

                  (a) If any change is made in the stock subject to the Plan, or
subject to any rights granted under the Plan (through merger, consolidation,
reorganization, recapitalization, stock dividend, dividend in property other
than cash, stock split, liquidating dividend, combination of shares, exchange of
shares, change in corporate structure or otherwise), the Plan and outstanding
rights will be appropriately adjusted in (i) the class(es) and maximum number of
shares subject to the Plan, (ii) the class(es), and number of shares and price
per share of stock subject to outstanding rights and (iii) any share limitations
established by the Board with respect to an offering.

                  (b) In the event of: (1) a dissolution or liquidation of the
Company; (2) a merger or consolidation in which the Company is not the surviving
corporation; (3) a reverse merger in which the Company is the surviving
corporation but the shares of the Company's Common Stock outstanding immediately
preceding the merger are converted by virtue of the merger into other property,
whether in the form of securities, cash or otherwise; or (4) any other capital
reorganization in which more than fifty percent (50%) of the shares of the
Company entitled to vote are exchanged, then, as determined by the Board in its
sole discretion (i) any surviving corporation may assume outstanding rights or
substitute similar rights for those under the Plan, (ii) such rights may
continue in full force and effect, or (iii) participants' accumulated payroll
deductions may be used to purchase Common Stock immediately prior to the
transaction described above and the participants' rights under the ongoing
Offering terminated.

         13.      AMENDMENT OF THE PLAN.

                  (a) The Board at any time, and from time to time, may amend
the Plan. However, except as provided in paragraph 12 relating to adjustments
upon changes in stock, no amendment shall be effective unless approved by the
stockholders of the Company within twelve (12) months before or after the
adoption of the amendment, where the amendment will:

                           (i)   Increase the number of shares reserved for
rights under the Plan;


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                           (ii)  Modify the provisions as to eligibility for
participation in the Plan (to the extent such modification requires
stockholder approval in order for the Plan to obtain employee stock purchase
plan treatment under Section 423 of the Code or to comply with the
requirements of Rule 16b-3 promulgated under the Securities Exchange Act of
1934, as amended ("Rule 16b-3")); or

                           (iii) Modify the Plan in any other way if such
modification requires stockholder approval in order for the Plan to obtain
employee stock purchase plan treatment under Section 423 of the Code or to
comply with the requirements of Rule 16b-3.

It is expressly contemplated that the Board may amend the Plan in any respect
the Board deems necessary or advisable to provide eligible employees with the
maximum benefits provided or to be provided under the provisions of the Code and
the regulations promulgated thereunder relating to employee stock purchase plans
and/or to bring the Plan and/or rights granted under it into compliance
therewith.

                  (b) Rights and obligations under any rights granted before
amendment of the Plan shall not be altered or impaired by any amendment of the
Plan, except with the consent of the person to whom such rights were granted or
except as necessary to comply with any laws or governmental regulation.

         14.      TERMINATION OR SUSPENSION OF THE PLAN.

                  (a) The Board may suspend or terminate the Plan at any time.
No rights may be granted under the Plan while the Plan is suspended or after it
is terminated.

                  (b) Rights and obligations under any rights granted while the
Plan is in effect shall not be altered or impaired by suspension or termination
of the Plan, except with the consent of the person to whom such rights were
granted or except as necessary to comply with any laws or governmental
regulation.

         15.      EFFECTIVE DATE OF PLAN.

                  The Plan shall become effective as determined by the Board,
but no rights granted under the Plan shall be exercised unless and until the
Plan has been approved by the stockholders of the Company.


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