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                                                                     EXHIBIT 4.3



                             WASTE MANAGEMENT, INC.
                          EMPLOYEE STOCK PURCHASE PLAN

                (AS AMENDED AND RESTATED EFFECTIVE MAY 16, 2003)

         The Waste Management, Inc. Employee Stock Purchase Plan (the "Plan")
has been established for the benefit of its eligible employees. The terms of the
Plan are set forth below.

                  1.       Definitions.

                  As used in the Plan the following terms shall have the
meanings set forth below:

                  (a) "Board" means the Board of Directors of the Company.

                  (b) "Code" means the Internal Revenue Code of 1986, as
         amended, and the regulations issued thereunder.

                  (c) "Committee" means the Administrative Committee of the
         Waste Management Employee Benefit Plans appointed by the Board to
         administer the Plan as described in Section 4 below.

                  (d) "Common Stock" means the common stock, $0.01 par value, of
         the Company.

                  (e) "Company" means Waste Management, Inc., a Delaware
         corporation, or any successor corporation by merger, reorganization,
         consolidation or otherwise.

                  (f) "Continuous Employment" means the absence of any
         interruption or termination of service as an Eligible Employee with the
         Company and/or its Participating Subsidiaries. For purposes of the
         preceding sentence, an authorized leave of absence shall not be
         considered an interruption or termination of service, provided that
         such leave is for a period of not more than 90 days or reemployment
         upon the expiration of such leave is guaranteed by contract or statute.

                  (g) "Eligible Compensation" means, with respect to each
         Participant for each pay period, the regular base earnings,
         commissions, overtime and, for employees on an Involuntary Military
         Leave of Absence, pay differential, paid to the Participant by the
         Company and/or one or more Participating Subsidiaries during the
         Offering Period before reductions are made to Code Section 125 and
         Section 401(k) plans maintained by the Company and/or its Participating
         Subsidiaries. However, any incentive compensation or other bonus
         amounts shall be excluded for purposes of determining Eligible
         Compensation.

                  (h) "Eligible Employee" means an employee of the Company or
         one of its Participating Subsidiaries who is customarily employed for
         at least 20 hours per week and more than five months in a calendar
         year, or are absent from active employment while on an Involuntary
         Military Leave of Absence. For purposes of the preceding sentence,
         employees who are members of a collective bargaining unit shall be
         excluded as eligible employees under the Plan, unless their applicable
         collective bargaining agreement provides for participation in the Plan.

                  (i) "Enrollment Date" means the first business day of each
         Offering Period.

                  (j) "Exercise Date" means the last business day of each
         Offering Period.


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                  (k) "Exercise Price" means the price per share of Common Stock
         offered in a given Offering Period, which shall be the lower of: (i)
         85% of the Fair Market Value of a share of the Common Stock on the
         Enrollment Date of such Offering Period, or (ii) 85% of the Fair Market
         Value of a share of the Common Stock on the Exercise Date of such
         Offering Period.

                  (l) "Fair Market Value" means, with respect to a share of
         Common Stock as of any Enrollment Date or Exercise Date, the closing
         price of such Common Stock on the New York Stock Exchange on such date,
         as reported in The Wall Street Journal. In the event that such a
         closing price is not available for an Enrollment Date or an Exercise
         Date, the Fair Market Value of a share of Common Stock on such date
         shall be the closing price of a share of the Common Stock on the New
         York Stock Exchange on the last business day prior to such date or such
         other amount as may be determined by the Committee by any fair and
         reasonable means.

                  (m) "Involuntary Military Leave of Absence" means an
         employee's leave from employment pursuant to the Company's Paid Leave
         of Absence Policy to perform military service obligations in the United
         States Air Force, Army, Navy, Marines, Coast Guard, Public Health
         Service Corps or National Guard, and the employee is either drafted or
         a member of the Reserves called to active duty.

                  (n) "Offering Period" means each six-month period that begins
         and ends on the business days that coincide with January 1 through June
         30, or July 1 through December 31, or such other period or periods as
         the Committee may establish. However, if the first and/or last day of
         an Offering Period begins or ends (as applicable) on a Saturday, Sunday
         or holiday, then (i) the first day of the Offering Period will begin on
         the immediately following business day, and/or (ii) the last day of an
         Offering Period will end on the immediately preceding business day.

                  (o) "Participant" means an Eligible Employee who has elected
         to participate in the Plan by filing an enrollment agreement with the
         Company as provided below in Section 6.

                  (p) "Participating Subsidiary" means any Subsidiary not
         excluded from participation in the Plan by the Committee, in its sole
         discretion.

                  (q) "Subsidiary" means any domestic or foreign corporation of
         which the Company owns, directly or indirectly, 50% or more of the
         total combined voting power of all classes of stock or other equity
         interests and that otherwise qualifies as a "subsidiary corporation"
         within the meaning of Section 424(f) of the Code or any successor
         thereto.

                  2.       Purpose of the Plan.

                  The purpose of the Plan is to provide an incentive for present
and future employees of the Company and its Participating Subsidiaries to
acquire a proprietary interest (or increase an existing proprietary interest) in
the Company through the purchase of Common Stock. The Company intends that the
Plan qualify as an "employee stock purchase plan" under Section 423 of the Code,
and that the Plan shall be administered, interpreted and construed in a manner
consistent with the requirements of Section 423 of the Code.

                  3.       Shares Reserved for the Plan.

                  The Company shall reserve for issuance and purchase by
Participants under the Plan an aggregate of 4,250,000 shares of Common Stock,
subject to adjustment as provided below in Section 13. Shares of Common Stock
subject to the Plan may be newly issued shares or treasury shares. If and to the
extent that any option to purchase shares of Common Stock shall not be exercised
for any reason, or if such right to purchase shares shall terminate as provided
herein, the shares that have not been so purchased hereunder shall again become
available for the purposes of the Plan, unless the Plan shall have been
terminated.


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                  4.       Administration of the Plan.

                  (a) A Committee appointed by the Board shall administer the
         Plan. The Committee shall have the authority to interpret the Plan, to
         prescribe, amend and rescind rules and regulations relating to the
         Plan, to correct any defect or rectify any omission in the Plan, or to
         reconcile any inconsistency in this Plan and any option to purchase
         shares granted hereunder, and to make all other determinations
         necessary or advisable for the administration of the Plan. The
         Committee's actions and determinations with respect to the foregoing
         shall be final, conclusive and binding on all persons. The act or
         determination of a majority of the members of the Committee shall be
         deemed to be the act or determination of the entire Committee.

                  (b) The Committee may, in its discretion, request advice or
         assistance, or employ such other persons as it deems necessary or
         appropriate for the proper administration of the Plan, including, but
         not limited to employing a brokerage firm, bank or other financial
         institution to assist in the purchase of shares, delivery of reports or
         other administrative aspects of the Plan.

                  5.       Eligibility to Participate in the Plan.

                  Subject to limitations imposed by Section 423(b) of the Code,
each Eligible Employee who is employed by the Company or a Participating
Subsidiary for 30 days prior to an Enrollment Date shall be eligible to
participate in the Plan for the Offering Period beginning on that Enrollment
Date.

                  6.       Election to Participate in the Plan.

                  (a) Each Eligible Employee may elect to participate in the
         Plan by completing an enrollment agreement in the form provided by the
         Company and filing such enrollment agreement with the Company prior to
         the applicable Enrollment Date, unless the Committee establishes
         another deadline for filing the enrollment agreement with respect to a
         given Offering Period.

                  (b) Unless a Participant withdraws from participation in the
         Plan as provided in Section 10 or authorizes a different payroll
         deduction by filing a new enrollment agreement prior to the Enrollment
         Date of a succeeding Offering Period, a Participant who is
         participating in an Offering Period as of the Exercise Date of such
         Offering Period shall be deemed to have (i) elected to participate in
         the immediately succeeding Offering Period and (ii) authorized the same
         payroll deduction percentage for such immediately succeeding Offering
         Period as was in effect for such Participant immediately prior to such
         succeeding Offering Period.

                  7.       Payroll Deductions.

                  (a) All Participant contributions to the Plan shall be made
         only by payroll deductions. Each time a Participant files the
         enrollment agreement with respect to an Offering Period, the
         Participant shall authorize payroll deductions to be made during the
         Offering Period in an amount from 1% to 10% (in whole percentages) of
         the Eligible Compensation that the Participant receives on each payroll
         date during such Offering Period. Payroll deductions for a Participant
         shall commence on the first payroll date following the Enrollment Date
         and shall end on the last payroll date in the Offering Period to which
         such authorization is applicable, unless sooner terminated by the
         Participant as provided below in Section 10.

                  (b) All payroll deductions made for a Participant shall be
         deposited in the Company's general corporate account and shall be
         credited to the Participant's account under the Plan. No interest shall
         accrue on or be credited with respect to the payroll deductions of a
         Participant under the Plan. A Participant may not make any additional
         contributions into such account. All payroll deductions received or
         held by the Company under the Plan may be used by the Company for any
         corporate purpose, and the Company shall not be obligated to segregate
         such payroll deductions.

                  (c) Except as provided in Section 10, a Participant may not
         change his contribution election during an Offering Period.


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                  (d) Notwithstanding the foregoing provisions of this Section
         7, no Participant may make payroll deductions during any calendar year
         in excess of $21,250, or such other limit as may be established by the
         Committee, in its discretion.

                  8.       Grant of Options.

                  (a) On the Enrollment Date of each Offering Period, subject to
         the limitations set forth in Sections 3 and 8(b) hereof, each Eligible
         Employee shall be granted an option to purchase on the Exercise Date
         for such Offering Period a number of whole and fractional shares of the
         Company's Common Stock determined by dividing such Eligible Employee's
         payroll deductions accumulated during the Offering Period by the
         Exercise Price established for such Offering Period.

                  (b) Notwithstanding any provision of the Plan to the contrary,
         no Eligible Employee shall be granted an option under the Plan (i) if,
         immediately after the grant, such Eligible Employee (or any other
         person whose stock would be attributed to such Employee pursuant to
         Section 424(d) of the Code) would own stock and/or hold outstanding
         options to purchase stock possessing 5% or more of the total combined
         voting power or value of all classes of stock of the Company or of any
         Subsidiary of the Company, or (ii) which permits such Eligible
         Employee's rights to purchase stock under all employee stock purchase
         plans of the Company and its Subsidiaries to accrue at a rate which
         exceeds $25,000 of fair market value of such stock (determined at the
         time such option is granted) for each calendar year in which such
         option is outstanding at any time.

                  9.       Automatic Purchase.

                  Unless a Participant withdraws from the Plan as provided below
in Section 10, the Participant's option for the purchase of shares will be
exercised automatically on each Exercise Date for which an enrollment agreement
has been filed, and the maximum number of whole and fractional shares subject to
the option will be purchased for the Participant at the Exercise Price
established for that Offering Period, as provided above in Section 8.

                  10.      Withdrawal; Termination of Employment.

                  (a) A Participant may withdraw all of the payroll deductions
         credited to the Participant's account for a given Offering Period by
         providing written notice to the Company no later than 45 days prior to
         the last day of such Offering Period. A Participant shall not be
         permitted to make a partial withdrawal of the payroll deductions
         credited to his account. All of the Participant's payroll deductions
         credited to the Participant's account will be paid to him promptly
         after receipt of the Participant's notice of withdrawal, the
         Participant's participation in the Plan will be automatically
         terminated, and no further payroll deductions for the purchase of
         shares hereunder will be made. Payroll deductions will not resume on
         behalf of a Participant who has withdrawn from the Plan, unless written
         notice is delivered to the Company within the enrollment period
         preceding the commencement of a new Offering Period directing the
         Company to resume payroll deductions.

                  (b) Upon termination of the Participant's Continuous
         Employment prior to the Exercise Date of the Offering Period for any
         reason, including retirement or death, the payroll deductions credited
         to the Participant's account will be returned to the Participant or, in
         the case of death, to the Participant's estate, and the Participant's
         options to purchase shares under the Plan will be automatically
         terminated.

                  (c) In the event a Participant ceases to be an Eligible
         Employee during an Offering Period, the Participant will be deemed to
         have elected to withdraw all payroll deductions credited to his account
         from the Plan. In such circumstance, the payroll deductions credited to
         the Participant's account will be returned to the Participant, and the
         Participant's options to purchase shares under the Plan will be
         terminated.

                  11.      Transferability.

                  Options to purchase Common Stock granted under the Plan are
not transferable, in any manner, by a Participant and are exercisable only by
the Participant.


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                  12.      Reports.

                  Individual accounts will be maintained for each Participant in
the Plan. Following each Exercise Date, statements of account will be given to
Participants who have purchased shares under Section 9. Such statements will set
forth the amounts of payroll deductions, the per share purchase price, the
number of shares purchased and the remaining cash balance, if any.

                  13.      Adjustments Upon Changes in Capitalization.

                  (a) If the outstanding shares of Common Stock are increased or
         decreased, or are changed into or are exchanged for a different number
         or kind of shares, as a result of one or more reorganizations,
         restructurings, recapitalizations, reclassifications, stock splits,
         reverse stock splits, stock dividends or the like, upon authorization
         of the Committee, appropriate adjustments shall be made in the number
         and/or kind of shares, and the per share purchase price thereof, which
         may be issued in the aggregate and to any Participant upon exercise of
         options granted under the Plan.

                  (b) In the event of the proposed dissolution or liquidation of
         the Company, each Offering Period will terminate immediately prior to
         the consummation of such proposed action, unless otherwise provided by
         the Committee. In the event of a proposed sale of all or substantially
         all of the assets of the Company, or the merger of the Company with or
         into another corporation, each option under the Plan shall be assumed
         or an equivalent option shall be substituted by such successor
         corporation or a parent or subsidiary of such successor corporation,
         unless the Committee determines, in the exercise of its sole discretion
         and in lieu of such assumption or substitution, that the Participant
         shall have the right to exercise the option as to all of the optioned
         stock, including shares as to which the option would not otherwise be
         exercisable. If the Committee makes an option fully exercisable in lieu
         of assumption or substitution in the event of a merger or sale of
         assets, the Committee shall notify the Participant that the option
         shall be fully exercisable for a stated period, which shall not be less
         than 10 days from the date of such notice, and the option will
         terminate upon the expiration of such period.

                  (c) In all cases, the Committee shall have full discretion to
         exercise any of the powers and authority provided under this Section
         13, and the Committee's actions hereunder shall be final and binding on
         all Participants. No fractional shares of stock shall be issued under
         the Plan pursuant to any adjustment authorized under the provisions of
         this Section 13.

                  14.      Amendment of the Plan.

                  The Board may at any time, or from time to time, amend the
Plan in any respect; provided, however, that the Plan may not be amended in any
way that will cause rights issued under the Plan to fail to meet the
requirements for employee stock purchase plans as defined in Section 423 of the
Code or any successor thereto, including, without limitation, shareholder
approval, if required.

                  15.      Termination of the Plan.

                  The Plan and all rights of Eligible Employees hereunder shall
terminate:

                  (a) on the Exercise Date that Participants become entitled to
                  purchase a number of shares greater than the number of
                  reserved shares remaining available for purchase under the
                  Plan; or

                  (b)      at any time, at the discretion of the Board.

                  In the event that the Plan terminates under circumstances
described in Section 15(a) above, reserved shares remaining as of the
termination date shall be sold to Participants on a pro rata basis.


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                  16.      Notices.

                  All notices or other communications by a Participant to the
Company under or in connection with the Plan shall be deemed to have been duly
given when received in the form specified by the Company at the location, or by
the person, designated by the Company for the receipt thereof.

                  17.      Shareholder Approval.

                  The Plan shall be subject to approval by the shareholders of
the Company within twelve months after the date the Plan is adopted by the Board
of Directors. If such shareholder approval is not obtained prior to the first
Exercise Date, the Plan shall be null and void and all Participants shall be
deemed to have withdrawn all payroll deductions credited to their accounts on
such Exercise Date pursuant to Section 10.

                  18.      Conditions Upon Issuance of Shares.

                  (a) The Plan, the grant and exercise of options to purchase
         shares of Common Stock under the Plan, and the Company's obligation to
         sell and deliver shares upon the exercise of options to purchase shares
         shall be subject to all applicable federal, state and foreign laws,
         rules and regulations, and to such approvals by any regulatory or
         governmental agency as may, in the opinion of counsel for the Company,
         be required. Notwithstanding anything in the Plan to the contrary,
         share certificates shall not be delivered to Participants until the
         later of (i) the date on which the applicable holding period to avoid a
         disqualifying disposition (within the meaning of Code Section 421)
         expires, or (ii) the date that a Participant specifically requests a
         certificate for shares purchased pursuant to the Plan.

                  (b) The Company may make such provisions, as it deems
         appropriate, for withholding by the Company pursuant to all applicable
         tax laws of such amounts as the Company determines it is required to
         withhold in connection with the purchase or sale by a Participant of
         any Common Stock acquired pursuant to the Plan. The Company may require
         a Participant to satisfy any relevant tax requirements before
         authorizing any issuance of Common Stock to such Participant.