GENZYME CORPORATION

                           2001 EQUITY INCENTIVE PLAN

1.       PURPOSE.

         The purpose of the Genzyme Corporation 2001 Equity Incentive Plan (the
"Plan") is to attract and retain key employees and consultants of the Company
and its Affiliates, to provide an incentive for them to achieve long-range
performance goals, and to enable them to participate in the long-range growth of
the Company by granting Awards with respect to the Company's Common Stock.
Certain capitalized terms used herein are defined in Section 8 below.

         The Plan constitutes an amendment and restatement of the Company's 1990
Equity Incentive Plan (the "Prior Plan"), which is hereby merged with and into
the Plan, and the separate existence of the Prior Plan shall terminate on the
effective date of the Plan. The rights and privileges of holders of outstanding
options and rights under the Prior Plan shall not be adversely affected by the
foregoing action.

2.       ADMINISTRATION.

         The Plan shall be administered by the Committee; provided, that the
Board may in any instance perform any of the functions of the Committee
hereunder. The Committee shall select the Participants to receive Awards and
shall determine the terms and conditions of the Awards. The Committee shall have
authority to adopt, alter and repeal such administrative rules, guidelines and
practices governing the operation of the Plan as it shall from time to time
consider advisable, and to interpret the provisions of the Plan. The Committee's
decisions shall be final and binding. To the extent permitted by applicable law,
the Committee may delegate to one or more executive officers of the Company the
power to make Awards to Participants who are not Reporting Persons or Covered
Employees and all determinations under the Plan with respect thereto, provided
that the Committee shall fix the maximum amount of such Awards for all such
Participants and a maximum for any one Participant.

3.       ELIGIBILITY.

         All employees and consultants of the Company or any Affiliate capable
of contributing significantly to the successful performance of the Company,
other than a person who has irrevocably elected not to be eligible, are eligible
to be Participants in the Plan. Incentive Stock Options may be granted only to
persons eligible to receive such Options under the Code.

4.       STOCK AVAILABLE FOR AWARDS.

         (a) AMOUNT. Subject to adjustment under subsection (b), Awards may be
made under the Plan for the following shares:

                                                                      GENZYME
                                          GENZYME       GENZYME      MOLECULAR
                                          GENERAL      BIOSURGERY     ONCOLOGY
                                           STOCK         STOCK         STOCK

    Options outstanding - Prior Plan     6,102,061     1,072,358     1,232,269
    Available for grant - Prior Plan        80,099       331,111       224,722
    NEW SHARES                           2,000,000     1,000,000       400,000
                                         ---------     ---------     ----------
    Total authorized shares              8,182,160     2,403,469     1,856,991




If any Award (including any Award under the Prior Plan) expires or is terminated
unexercised or is forfeited or settled in a manner that results in fewer shares
outstanding than were awarded, the shares subject to such Award, to the extent
of such expiration, termination, forfeiture or decrease, shall again be
available for award under the Plan. Common Stock issued through the assumption
or substitution of outstanding grants from an acquired company shall not reduce
the shares available for Awards under the Plan. Shares issued under the Plan may
consist of authorized but unissued shares or treasury shares.

         (b) ADJUSTMENT. In the event that the Committee determines that any
stock dividend, extraordinary cash dividend, re-capitalization, reorganization,
merger, consolidation, split-up, spin-off, combination, exchange of shares or
other transaction affects the Common Stock such that an adjustment is required
in order to preserve the benefits intended to be provided by the Plan, then the
Committee (subject in the case of Incentive Stock Options to any limitation
required under the Code) shall equitably adjust any or all of (i) the number and
kind of shares in respect of which Awards may be made under the Plan, (ii) the
number and kind of shares subject to outstanding Awards and (iii) the exercise
price with respect to any of the foregoing, provided that the number of shares
subject to any Award shall always be a whole number, and if considered
appropriate, the Committee may make provision for a cash payment with respect to
an outstanding Award. Notwithstanding the foregoing, unless otherwise determined
by the Committee, no adjustment will be made for dividends of one series of
Common Stock paid on another series of Common Stock. No adjustment to decrease
the exercise price of outstanding stock options granted under the plan with
respect to a repricing program will be made without shareholder approval.

         (c) LIMIT ON INDIVIDUAL GRANTS. Subject to adjustment under subsection
(b), the maximum number of shares subject to Options that may be granted to any
Participant in the aggregate in any calendar year shall not exceed 1,000,000
shares of Genzyme General Stock, 1,000,000 shares of Genzyme Biosurgery Stock,
and 1,000,000 shares of Genzyme Molecular Oncology Stock, and the maximum number
of shares that may be granted as Restricted Stock or unrestricted stock Awards,
with respect to which performance goals apply under Section 6 below, to any
Participant in the aggregate in any calendar year shall not exceed 1,000,000
shares of Genzyme General Stock, 1,000,000 shares of Genzyme Biosurgery Stock,
and 1,000,000 shares of Genzyme Molecular Oncology Stock.

5.       STOCK OPTIONS.

         (a) GRANT OF OPTIONS. Subject to the provisions of the Plan, the
Committee may grant options ("Options") to purchase shares of Common Stock (i)
complying with the requirements of Section 422 of the Code or any successor
provision and any regulations thereunder ("Incentive Stock Options") and (ii)
not intended to comply with such requirements ("Nonstatutory Stock Options").
The Committee shall determine the number of shares subject to each Option and
the exercise price therefor, which shall not be less than 100% of the Fair
Market Value of the Common Stock on the date of Grant, provided that a
Nonstatutory Stock Option granted to a new employee or consultant in connection
with the hiring of such person may have a lower exercise price so long as it is
not less than 100% of Fair Market Value on the date the person accepts the
Company's offer of employment or the date employment commences, whichever is
lower. No Options may be granted hereunder more than ten years after the
effective date of the Plan.

         (b) TERMS AND CONDITIONS. Each Option shall be exercisable at such
times and subject to terms and conditions as the Committee may specify in the
applicable grant or thereafter. The Committee may impose such conditions with
respect to the exercise of Options, including conditions relating to applicable
federal or state securities laws, as it considers necessary or advisable.




         (c) PAYMENT. No shares shall be delivered pursuant to any exercise of
an Option until payment in full of the exercise price therefor is received by
the Company. Such payment may be made in whole or in part in cash or, to the
extent permitted by the Committee at or after the grant of the Option, by
delivery of a note or other commitment satisfactory to the Committee or shares
of Common Stock owned by the optionee (which shares must be owned for at least
six months) valued at their Fair Market Value on the date of delivery, or such
other lawful consideration, including a payment commitment of a financial or
brokerage institution, as the Committee may determine.

6.       STOCK AWARDS.

         (a) GRANT OF RESTRICTED OR UNRESTRICTED STOCK AWARDS. The Committee may
grant shares of Common Stock subject to forfeiture ("Restricted Stock") and
determine the duration of the period (the "Restricted Period") during which, and
the conditions under which, the shares may be forfeited to the Company and the
other terms and conditions of such Awards. Shares of Restricted Stock may not be
sold, assigned, transferred, pledged or otherwise encumbered, except as
permitted by the Committee, during the Restricted Period. Shares of Restricted
Stock shall be evidenced in such manner as the Committee may determine. Any
certificates issued in respect of shares of Restricted Stock shall be registered
in the name of the Participant and unless otherwise determined by the Committee,
deposited by the Participant, together with a stock power endorsed in blank,
with the Company. At the expiration of the Restricted Period, the Company shall
deliver such certificates to the Participant or if the Participant has died, to
the Participant's Designated Beneficiary. The Committee also may make Awards of
shares of Common Stock that are not subject to restrictions or forfeiture, on
such terms and conditions as the Committee may determine from time to time.
Shares of Restricted Stock or unrestricted stock may be issued for no cash
consideration, such minimum consideration as may be required by applicable law
or such other consideration as the Committee may determine.

         (b) PERFORMANCE GOALS. The Committee may establish performance goals
for the granting of Restricted Stock or unrestricted stock Awards or the lapse
of risk of forfeiture of Restricted Stock. Such performance goals may be based
on one or more of the following criteria selected by the Committee, measured
either absolutely or relative to an index, and as applied to the Company or any
subsidiary, division or product line thereof: total shareholder return or stock
price; earnings per share; net earnings; consolidated pre-tax earnings;
revenues; operating income; earnings before interest and taxes; sales or expense
targets; cash flow; return on equity; return on net assets employed or earnings
per share; value created; operating margin; and strategic business criteria,
consisting of one or more objectives based on meeting specified market
penetration, geographic business expansion goals, and goals relating to research
or product development, acquisitions or divestitures; or such other business
criteria as the Committee may determine.

7.       GENERAL PROVISIONS APPLICABLE TO AWARDS.

         (a) DOCUMENTATION. Each Award under the Plan shall be evidenced by a
writing delivered to the Participant or agreement executed by the Participant
specifying the terms and conditions thereof and containing such other terms and
conditions not inconsistent with the provisions of the Plan as the Committee
considers necessary or advisable to achieve the purposes of the Plan or to
comply with applicable tax and regulatory laws and accounting principles.

         (b) COMMITTEE DISCRETION. Each type of Award may be made alone, in
addition to or in relation to any other Award. The terms of each type of Award
need not be identical, and the Committee need not treat Participants uniformly.
Except as otherwise provided by the Plan or a




particular Award, any determination with respect to an Award may be made by the
Committee at the time of grant or at any time thereafter.

         (c) DIVIDENDS AND CASH AWARDS. In the discretion of the Committee, any
Award under the plan may provide the Participant with (i) dividends or dividend
equivalents payable (in cash or in the form of Awards under the Plan) currently
or deferred with or without interest and (ii) cash payments in lieu of or in
addition to an Award.

         (d) TERMINATION OF SERVICE. The Committee shall determine the effect on
an Award of the disability, death, retirement or other termination of service of
a Participant and the extent to which, and the period during which, the
Participant's legal representative, guardian or Designated Beneficiary may
receive payment of an Award or exercise rights thereunder.

         (e) CHANGE IN CONTROL. In order to preserve a Participant's rights
under an Award in the event of a change in control of the Company (as defined by
the Committee), the Committee in its discretion may, at the time an Award is
made or at any time thereafter, take one or more of the following actions: (i)
provide for the acceleration of any time period relating to the exercise or
payment of the Award, (ii) provide for payment to the Participant of cash or
other property with a Fair Market Value equal to the amount that would have been
received upon the exercise or payment of the Award had the Award been exercised
or paid upon the change in control, (iii) adjust the terms of the Award in a
manner determined by the Committee to reflect the change in control, (iv) cause
the Award to be assumed, or new rights substituted therefor, by another entity,
or (v) make such other provision as the Committee may consider equitable to
Participants and in the best interests of the Company.

         (f) LOANS. The Committee may authorize the making of loans or cash
payments to Participants in connection with the grant or exercise of any Award
under the Plan, which loans may be secured by any security, including Common
Stock, underlying or related to such Award (provided that the loan shall not
exceed the Fair Market Value of the security subject to such Award), and which
may be forgiven upon such terms and conditions as the Committee may establish at
the time of such loan or at any time thereafter.

         (g) TRANSFERABILITY. In the discretion of the Committee, any Award may
be made transferable upon such terms and conditions and to such extent as the
Committee determines, provided that Incentive Stock Options may be transferable
only to the extent permitted by the Code. The Committee may in its discretion
waive any restriction on transferability.

         (h) WITHHOLDING TAXES. The Participant shall pay to the Company, or
make provision satisfactory to the Committee for payment of, any taxes required
by law to be withheld in respect of Awards under the Plan no later than the date
of the event creating the tax liability. The Company and its Affiliates may, to
the extent permitted by law, deduct any such tax obligations from any payment of
any kind due to the Participant hereunder or otherwise. In the Committee's
discretion, the minimum tax obligations required by law to be withheld in
respect of Awards may be paid in whole or in part in shares of Common Stock,
including shares retained from the Award creating the tax obligation, valued at
their Fair Market Value on the date of retention or delivery.

         (i) FOREIGN NATIONALS. Awards may be made to Participants who are
foreign nationals or employed outside the United States on such terms and
conditions different from those specified in the Plan as the Committee considers
necessary or advisable to achieve the purposes of the Plan or to comply with
applicable laws.

         (j) AMENDMENT OF AWARD. The Committee may amend, modify or terminate
any outstanding Award, including substituting therefor another Award of the same
or a different type, changing the date of exercise or realization and converting
an Incentive Stock Option to a




Nonstatutory Stock Option, provided that the Participant's consent to such
action shall be required (a) if such action would terminate, or reduce the
number of shares issuable under an Option, unless any time period relating to
the exercise of such Option or the eliminated portion, as the case may be, is
accelerated before such termination or reduction, in which case the Committee
may provide for the Participant to receive cash or other property equal to the
net value that would be received upon exercise of the terminated Option or the
eliminated portion, as the case may be, and (b) in any other case, unless the
Committee determines that the action, taking into account any related action,
would not materially and adversely affect the Participant. No adjustment to
decrease the exercise price of outstanding stock options granted under the plan
with respect to a repricing program will be made without shareholder approval.

8.       CERTAIN DEFINITIONS.

         "Affiliate" means any business entity in which the Company owns
directly or indirectly 50% or more of the total voting power or has a
significant financial interest as determined by the Committee.

         "Award" means any Option or Stock granted under the plan.

         "Board" means the Board of Directors of the Company.

         "Code" means the Internal Revenue Code of 1986, as amended from time to
time, or any successor law.

         "Committee" means one or more committees each comprised of not less
than two members of the Board appointed by the Board to administer the Plan or a
specified portion thereof. Unless otherwise determined by the Board, if a
Committee is authorized to grant Awards to a Reporting Person or a Covered
Employee, each member shall be a "non-employee director" within the meaning of
Rule 16b-3 under the Exchange Act or an "outside director" within the meaning of
Section 162(m) of the Code, respectively.

         "Common Stock" or "Stock" means the Genzyme General Stock, the Genzyme
Biosurgery Stock, the Genzyme Molecular Oncology Stock and any other series of
Common Stock, $.01 par value, of the Company.

         "Company" means Genzyme Corporation.

         "Covered Employee" means a "covered employee" within the meaning of
Section 162(m) of the code.

         "Designated Beneficiary" means the beneficiary designated by a
Participant, in a manner determined by the Committee, to receive amounts due or
exercise rights of the Participant in the event of the Participant's death. In
the absence of an effective designation by a Participant, "Designated
Beneficiary" means the Participant's estate.

         "Exchange Act" means the Securities Exchange Act of 1934, as amended
from time to time, or any successor law.

         "Fair Market Value" means, with respect to Common Stock or any other
property, the Fair Market Value of such property as determined by the Committee
in good faith or in the manner established by the Committee from time to time.

         "Genzyme General Stock" means the Genzyme General Division Common
Stock.




         "Genzyme Biosurgery Stock" means the Genzyme Biosurgery Division Common
Stock.

         "Genzyme Molecular Oncology Stock" means the Genzyme Molecular Oncology
Division Common Stock.

         "Participant" means a person selected by the Committee to receive an
Award under the Plan.

         "Reporting Person" means a person subject to Section 16 of the Exchange
Act.

9.       MISCELLANEOUS.

         (a) NO RIGHT TO EMPLOYMENT. No person shall have any claim or right to
be granted an Award. Neither the adoption, maintenance, nor operation of the
Plan nor any Award hereunder shall confer upon any employee or consultant of the
Company or of any Affiliate any right with respect to the continuance of his or
her employment by or other service with the Company or any such Affiliate nor
shall they interfere with the rights of the Company (or Affiliate) to terminate
any employee at any time or otherwise change the terms of employment.

         (b) NO RIGHTS AS STOCKHOLDER. Subject to the provisions of the
applicable Award, no Participant or Designated Beneficiary shall have any rights
as a stockholder with respect to any shares of Common Stock to be issued under
the Plan until he or she becomes the holder thereof. A Participant to whom
Common Stock is awarded shall be considered the holder of the Stock at the time
of the Award except as otherwise provided in the applicable Award.

         (c) EFFECTIVE DATE. The Plan shall be effective on the date it is
approved by the stockholders.

         (d) AMENDMENT OF PLAN. The Board may amend, suspend or terminate the
Plan or any portion thereof at any time, subject to such stockholder approval as
the Board determines to be necessary or advisable to comply with any tax or
regulatory requirement.

         (e) GOVERNING LAW. The provisions of the Plan shall be governed by and
interpreted in accordance with the laws of the Commonwealth of Massachusetts.

                          Adopted by the Board of Directors on March 1, 2001
                          Approved by Stockholders on May 31, 2001


(7/01)