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                                                                    Exhibit 10.1


                              MILLIPORE CORPORATION
                            1999 STOCK INCENTIVE PLAN

1.       PURPOSE

The purpose of this 1999 Stock Incentive Plan (the "Plan") is to advance the
interests of Millipore Corporation (the "Company") and its subsidiaries by
enhancing the ability of the Company to (i) attract and retain employees and
other persons or entities who are in a position to make significant
contributions to the success of the Company and its subsidiaries; (ii) reward
such persons or entities for such contributions; and (iii) encourage such
persons or entities to take into account the long-term interest of the Company
through ownership of shares ("Shares") of the Company's common stock ("Stock").

         The Plan is intended to accomplish these goals by enabling the Company
to grant awards ("Awards") in the form of Options and Restricted Stock, all as
more fully described below.

2.       ADMINISTRATION

         The Plan will be administered by the Management Development and
Compensation Committee (the "Committee") of the Board of Directors of the
Company (the "Board"). The Plan and its administration will comply with Rule
16b-3 promulgated under the Securities Exchange Act of 1934, as amended (the
"Exchange Act"), or any successor rule and will comply with the requirements of
Section 162(m) of the Internal Revenue Code of 1986, as amended (the "Code").
The Committee will determine the recipients of Awards, the times at which Awards
will be made and the size and type or types of Awards to be made to each
recipient and will set forth in such Awards the terms, conditions and
limitations applicable to it. Awards may be made singly, in combination or in
tandem. The Committee will have full and exclusive power to interpret the Plan,
to adopt rules, regulations and guidelines relating to the Plan, to grant
waivers of Plan restrictions and to make all of the determinations necessary for
its administration. Such determinations and actions of the Committee, and all
other determinations and actions of the Committee made or taken under authority
granted by any provision of the Plan, will be conclusive and binding on all
parties. Nothing in this paragraph shall be construed as limiting the power of
the Committee or the Board to make adjustments under Section 12 or to amend or
terminate the Plan under Section 16.

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3.       EFFECTIVE DATE AND TERM OF PLAN

         The Plan will become effective on the date on which it is approved by
the stockholders of the Company. Grants of Awards under the Plan may be made
prior to that date, subject to such approval of the Plan.

         The Plan will terminate ten years after the effective date of the Plan,
subject to earlier termination of the Plan by the Board pursuant to Section 16.
No Award may be granted under the Plan after the termination date of the Plan,
but Awards previously granted may extend beyond that date.

4.       SHARES SUBJECT TO THE PLAN

         Subject to adjustment as provided in Section 11 below, (i) the maximum
aggregate number of Shares of Stock that may be delivered for all purposes under
the Plan shall be 9,563,605 (5,061,435 shares after giving effect to the Board
of Directors approval of an amendment in February 2002 increasing the number of
shares by 5,000,000 subject to approval by the Stockholders at the 2002 Annual
Meeting) and (ii) the maximum number of Options and Restricted Stock awarded to
any Participant (as defined in Section 5 below) in any calendar year under the
Plan shall be (x) 250,000 in the case of all Participants other than the Chief
Executive Officer and/or President of the Company and (y) 500,000 in the case of
the Chief Executive Officer and/or President of the Company. The maximum
aggregate number of Shares of Stock which may be issued under the Plan pursuant
to the exercise of ISOs (as defined in Section 7 below) shall be 1,000,000. The
maximum aggregate number of Shares of Stock which may be issued under the Plan
as Restricted Stock shall be 250,000.

         If any Award requiring exercise by the Participant for delivery of
Stock is canceled or terminates without having been exercised in full, the
number of Shares of Stock as to which such Award was not exercised will be
available for future grants of stock. Shares of Stock tendered by a Participant
or withheld by the Company to pay the exercise price of an Option or to satisfy
the tax withholding obligations of the exercise or vesting of an Award shall be
available again for Awards under the Plan, but only to Participants who are not
subject to Section 16 of the Exchange Act. Shares of Restricted Stock forfeited
to the Company in accordance with the Plan and the terms of the particular Award
shall be available again for Awards under the Plan.

         Stock delivered under the Plan may be either authorized but unissued
Stock or previously issued Stock acquired by the Company and held in treasury.
No fractional Shares of Stock will be delivered under the Plan and the Committee
shall determine the manner in which fractional share value will be treated.

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5.       ELIGIBILITY AND PARTICIPATION

         Those eligible to receive Awards under the Plan ("Participants") will
be persons in the employ of the Company or any of its subsidiaries ("Employees")
and other persons or entities who, in the opinion of the Committee, are in a
position to make a significant contribution to the success of the Company or its
subsidiaries, except that non-Employee directors of the Company or a subsidiary
of the Company are not eligible to participate in this Plan. A "subsidiary" for
purposes of the Plan will be a corporation in which the Company owns, directly
or indirectly, stock possessing 50% or more of the total combined voting power
of all classes of stock.

6.       DELEGATION OF AUTHORITY

         The Committee may delegate to senior officers of the Company who are
also directors of the Company (including, without limitation, the Chief
Executive Officer and/or President) its duties under the Plan subject to such
conditions and limitations as the Committee may prescribe, except that only the
Committee may designate and make grants to Participants (i) who are subject to
Section 16 of the Exchange Act or any successor statute, including, without
limitation, decisions on timing, amount and pricing of Awards, or (ii) whose
compensation is covered by Section 162(m) of the Code.

7.       OPTIONS

         a. Nature of Options. An Option is an Award entitling the Participant
to purchase a specified number of Shares at a specified exercise price. Both
"incentive stock options," as defined in Section 422 of the Code (referred to
herein as an "ISO") and non-incentive stock options may be granted under the
Plan. ISOs may be awarded only to Employees.

         b. Exercise Price. The exercise price of each Option shall be
determined by the Committee, but in the case of an ISO shall not be less than
100% (110% in the case of an ISO granted to a ten-percent shareholder) of the
Fair Market Value of a Share at the time the ISO is granted; nor shall the
exercise price of any other Option be less than 100% of the Fair Market Value of
a Share at the time the Option is granted; provided, that, in no case shall the
exercise price of an Option be less, in the case of an original issue of
authorized Stock, than the par value of a Share. For purposes of this Plan,
"Fair Market Value" shall mean, except as provided below, the closing price of a
Share as reported on the New York Stock Exchange on the day prior to the date of
the grant (based on The Wall Street Journal report of composite transactions)
or, if the New York Stock Exchange is closed on the day prior to the date of
grant, the next preceding day on which it is open or, if the Shares are no
longer listed on such Exchange, such term shall have the same meaning as it does
in the case of ISOs. In the case of ISOs, the term

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"Fair Market Value" shall have the same meaning as it does in the provisions of
the Code and the regulations thereunder applicable to ISOs. For purposes of this
Plan, "ten-percent shareholder" shall mean any Employee who at the time of grant
owns directly, or is deemed to own by reason of the attribution rules set forth
in Section 424(d) of the Code, Stock possessing more than 10% of the total
combined voting power of all classes of stock of the Company or of any of its
subsidiaries.

         c. Duration of Options. In no case shall an Option be exercisable
more than ten years (five years, in the case of an ISO granted to a "ten-percent
shareholder" as defined in (b) above) from the date the Option was granted.

         d. Exercise of Options and Conditions. Options granted under any single
Award will become exercisable at such time or times, and on and subject to such
conditions, as the Committee may specify. The Committee may at any time and from
time to time accelerate the time at which all or any part of the Option may be
exercised.

         e. Payment for and Delivery of Stock. Full payment for Shares purchased
will be made at the time of the exercise of the Option, in whole or in part.
Payment of the purchase price will be made in cash or in such other form as the
Committee may approve, including, without limitation, delivery of Shares of
Stock.

8.       RESTRICTED STOCK

         A Restricted Stock Award entitles the recipient to acquire Shares,
subject to certain restrictions or conditions, for no cash consideration, if
permitted by applicable law, or for such other consideration as determined by
the Committee. The Award may be subject to such restrictions, conditions, and
forfeiture provisions as the Committee may determine, including, but not limited
to, restrictions on transfer; continuous service with the Company; achievement
of business objectives, and individual, unit and Company performance. Subject to
such restrictions, conditions and forfeiture provisions as may be established by
the Committee, any Participant receiving an Award will have all the rights of a
stockholder of the Company with respect to Shares of Restricted Stock, including
the right to vote the Shares and the right to receive any dividends thereon. In
the event of a Participant's death, any Restricted Stock previously awarded to
him shall become free of restrictions, unless at the time of its initial grant
the Committee has provided otherwise.

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9.       TRANSFERS AND TERMINATIONS

         a. No Award (other than an Award in the form of an outright transfer of
Stock) may be assigned, pledged or transferred other than by will or by the laws
of descent and distribution and during a Participant's lifetime will be
exercisable only by the Participant or, in the event of a Participant's
incapacity, his or her guardian or legal representative, except that with the
approval of the Board of Directors (and upon such terms and conditions imposed
by the Board) Participants may gift Options to immediate family members or
family trusts.

         b. If and when an employee Participant shall cease to be an employee of
the Company (or a subsidiary) any Award granted to him under this Plan shall,
except as otherwise provided in this Section 9(b), terminate. During the 90 day
period following the Participant's termination of employment, for reasons other
than "cause", the Participant shall have the right to exercise any Options
previously granted, vested and exercisable on the Participant's employment
termination date. In the event an employee is terminated for "cause", any Option
granted to him under this Plan shall terminate immediately.

            The Committee may provide for an optionee a special exercise period
which will apply if his employment terminates due to retirement at normal
retirement age (as defined in the Company's Retirement Plan) or he terminates
his employment earlier with the consent of the Company (the "Special Exercise
Period"). The Special Exercise Period will begin on the date of termination of
employment and end on the date specified by the Committee, but in no event later
than the earlier of the expiration date of the option or the fifth anniversary
of the date of termination of employment. During such period the option will be
exercisable to the extent it would have been exercisable had the Participant
remained in the employ of the Company.

            With respect to non-incentive stock options granted under the Plan
to employees, the Special Exercise Period shall apply without further consent of
the Committee if a Participant's employment with the Company terminates after
such Participant has attained age 62 and completed ten (10) years of Service (as
defined in the Company's Retirement Plan) with the Company.

            Any question whether or when a Participant has retired or terminated
his employment with the consent of the Company shall be determined by the
Committee, and its determination shall be final.

            If a Participant dies while employed by the Company (or a
subsidiary) or during a Special Exercise Period provided under this Section
9(b), his Option may be exercised in accordance with Section 10.

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         Notwithstanding any other provision contained in this Plan, the Company
shall have the right, but shall not be required, to repurchase from any employee
who terminates his employment without the consent and approval of the Company,
within six months of the exercise of any Option, the shares of the Company's
Common Stock so purchased by said employee at their original (or exercise)
price.

         c. In the event a Participant's employment with the Company terminates
after such Participant has attained the age of 62 and completed ten (10) years
of Service (as defined in the Company's Retirement Plan) with the Company, any
Restricted Stock previously granted to him under the Plan shall become free of
any and all restrictions.

         d. No award, nor anything contained in the Plan shall confer upon any
participant any right to continue in the Company's employ or limit in any way
the Company's right to terminate his employment at anytime. In no event shall
the loss of profit or potential profit in any award constitute an element of
damages in the event of termination of the employment relationship of the
participant, even if the termination is in violation of an obligation of the
Company or any of its subsidiaries.

10.      DEATH OF PARTICIPANT

         a. Should a participant die while in the employ of the Company (or a
subsidiary), or within a Special Exercise Period provided to him under Section
9, any Option held by him at death may be exercised by his estate, or by the
person or persons designated in his last will and testament, as follows: In the
case of death during employment, each Option will be exercisable until the
earlier of (1) the first anniversary of his death (or such earlier date as the
Committee may establish at the time of the grant) and (2) the original
expiration date of the Option to the extent the Option was exercisable by the
participant at the time of death. In the case of death during a Special Exercise
Period, each Option will be exercisable during the remainder of such period to
the extent it would have been exercisable had the employee lived.

11.      ADJUSTMENTS

         a. In the event of a stock dividend, stock split or combination of
Shares, recapitalization or other change in the Company's capitalization, or
other distribution to common stockholders other than normal cash dividends,
after the effective date of the Plan, the Committee will make any appropriate
adjustments to the maximum number of Shares that may be delivered under the Plan
and to any Participant under Section 4 above.

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         b. In any event referred to in paragraph (a), the Committee will also
make any appropriate adjustments to the number and kind of Shares of Stock or
securities subject to Awards then outstanding or subsequently granted, any
exercise prices relating to Awards and any other provision of Awards affected by
such change. The Committee may also make such adjustments to take into account
material changes in law or in accounting practices or principles, mergers,
consolidations, acquisitions, dispositions or similar corporate transactions, or
any other event, if it is determined by the Committee that adjustments are
appropriate to avoid distortion in the operation of the Plan.

         c. In the event that any option granted under the Millipore Corporation
1995 Combined Stock Option Plan, as Amended, or any restricted stock awarded
under the 1995 Long Term Restricted Stock (Incentive) Plan for Senior Management
shall expire or terminate or be forfeited under said Plans, then, in that event,
any such option or restricted stock shall be added to the number of Shares of
Stock that may delivered for all purposes under this Plan.

12.      RIGHTS AS A STOCKHOLDER

         Except as specifically provided by the Plan, the receipt of an Award
will not give a Participant rights as a stockholder; the Participant will obtain
such rights, subject to any limitations imposed by the Plan or the instrument
evidencing the Award, upon actual receipt of Shares.

13.      CONDITIONS ON DELIVERY OF STOCK

         The Company will not be obligated to deliver any Shares pursuant to the
Plan or to remove any restrictions or legends from Shares previously delivered
under the Plan until, (a) in the opinion of the Company's counsel, all
applicable federal and state laws and regulations have been complied with, (b)
if the outstanding Shares are at the time listed on any stock exchange, the
Shares to be delivered have been listed or authorized to be listed on such
exchange upon official notice of notice of issuance, and (c) all other legal
matters in connection with the issuance and delivery of such Shares have been
approved by the Company's counsel. If the sale of Shares has not been registered
under the Securities Act of 1933, as amended, the Company may require, as a
condition to exercise of the Award, such representations and agreements as
counsel for the Company may consider appropriate to avoid violation of such Act
and may require that the certificates evidencing such Shares bear an appropriate
legend restricting transfer.

         If an Award is exercised by the Participant's legal representative, the
Company will be under no obligation to deliver Shares pursuant to such exercise
until the Company is satisfied as to the authority of such representative.



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14.      TAX WITHHOLDING

         The Company will have the right to deduct from any cash payment under
the Plan taxes that are required to be withheld and further to condition the
obligation to deliver or vest Shares under this Plan upon the Participant's
paying the Company such amount as it may request to satisfy any liability for
applicable withholding taxes. The Committee may in its discretion permit
Participants to satisfy all or part of their withholding liability by delivery
of Shares with a Fair Market Value equal to such liability or by having the
Company withhold from Stock delivered upon exercise of an Award, Shares whose
Fair Market Value is equal to such liability.

15.      MERGERS; ETC.

         In the event of any merger or consolidation involving the Company, any
sale of substantially all of the Company's assets or any other transaction or
series of related transactions as a result of which a single person or several
persons acting in concert own a majority of the Company's then outstanding Stock
(such merger, consolidation, sale or other transaction being hereinafter
referred to as a "Transaction"), all outstanding Options shall, if the
Committee, so votes by a majority of the members of the Committee who are
Continuing Directors (as defined below), become immediately exercisable and each
outstanding share of Restricted Stock shall immediately become free of all
restrictions and conditions. In that event, upon consummation of the
Transaction, all outstanding Options shall terminate and cease to be
exercisable.

         In lieu of the foregoing, if there is an acquiring or surviving
corporation or equity, the Committee may, by vote of a majority of the members
of the Committee who are Continuing Directors, arrange to have such acquiring or
surviving corporation or entity or an Affiliate (as defined below) thereof grant
to Participants holding outstanding Awards replacement Awards which, in the case
of ISOs, satisfy, in the determination of the Committee, the requirements of
Section 424(a) of the Code.

         The term "Continuing Director" shall mean any director of the Company
who (i) is not an Acquiring Person or an Affiliate of an Acquiring Person and
(ii) either was (A) a member of the Board of Directors of the Company on the
date hereof or (B) nominated for his or her initial term of office by a majority
of the Continuing Directors in office at the time of such nomination. The term
"Acquiring Person" shall mean, with respect to any Transaction, each Person who
is a party to or a participant in such Transaction or who, as a result of such
Transaction, would (together with other Persons acting in concert) own a
majority of the Company's outstanding Common Stock; provided, however, that none
of the Company, any wholly-owned subsidiary of the Company, any employee benefit
plan of the Company or any trustee in respect thereof acting in such
capacity shall, for

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purposes of this Section, be deemed an "Acquiring Person". The term "Affiliate",
with respect to any Person, shall mean any other Person who is, or would
bedeemed to be, an "affiliate" or an "associate" of such Person within the
respective meanings ascribed to such terms in Rule 12b-2 of the General Rules
and Regulations under the Securities Exchange Act of 1934, as amended. The term
"Person" shall mean a corporation, association, partnership, joint venture,
trust, organization, business, individual or government or any governmental
agency or political subdivision thereof.

16.      AMENDMENTS AND TERMINATION

         The Committee will have the authority to make such amendments to any
terms and conditions applicable to outstanding Awards as are consistent with
this Plan provided that, except for adjustments under Section 11 hereof, no such
action will modify such Award in a manner adverse to the Participant without the
Participant's consent except as such modification is provided for or
contemplated in the terms of the Award. Notwithstanding the preceding sentence,
the Committee will not reprice any stock option (whether by modification of the
exercise price, replacement, or cancellation and regrant) without shareholder
approval.

         The Board may amend, suspend or terminate the Plan except that no such
action may be taken, without shareholder approval, which would effectuate any
change for which shareholder approval is required pursuant to Section 16 of the
Exchange Act.

17.      PRIOR PLANS

         This Plan is intended to replace the Millipore Corporation 1995
Combined Stock Option Plan, as amended and the 1995 Long Term Restricted Stock
(Incentive) Plan for Senior Management (collectively the "Prior Plans"), which
Prior Plans shall automatically be terminated and replaced and superseded by
this Plan on the date on which this Plan becomes effective, except that any
option or restricted stock granted under the Prior Plans shall remain in effect
pursuant to their terms.

18.      MISCELLANEOUS

         This Plan shall be governed by and construed in accordance with the
laws of The Commonwealth of Massachusetts.

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