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                                                                      EXHIBIT 10

Mr. Michael P. Carroll
2 Horizon Point
Frisco, Texas

Dear Mike:

The purpose of this Letter Agreement ("Agreement") is to set forth our agreement
with respect to the following matters: (a) the severance compensation and
benefits being offered to you as the result of our mutual agreement that the
Company accept your resignation as Vice President of  Millipore Corporation
("the Company") and General Manager of the Company's Microelectronics Gas
Process Division on February 15, 2001 ("Severance Date"); (b) reimbursement to
the Company of those sums  described as "Relocation Payback" expenses in the
Relocation Agreement dated November 10, 1999 ("Relocation Agreement"); and (c)
repayment to the Company of the $450,000.00 loan subject to the Relocation
Agreement and the Promissory Note dated December 9, 1999 and certain other
matters relating to your Frisco, Texas residence, all as more fully described
below.

     A.  SEVERANCE AND BENEFITS:

     (1) You will receive severance payments in the amount of two (2) years of
your current total annual target cash compensation ($843,570.00) less the tax
liability you incurred as the result of your assignment to Hong Kong
($76,108.00) and less the compensation paid to you after the Severance Date but
before the commencement of the severance payments hereunder ("Total Severance").
Total Severance, less appropriate deductions, will be paid to you in 52 equal
bi-weekly installments.

     (2) All unvested stock options previously granted to you shall become
immediately vested as of the Severance Date.  All of your options must be
exercised, if at all, no later than one year after the Severance Date.  All
restricted stock previously granted to you shall become free of all restrictions
on the Severance Date.

     (3) Millipore will provide you with medical and dental coverage until you
are eligible for coverage under another group health plan or until February 15,
2003, whichever occurs first, provided you continue to pay the applicable
employee contribution of the premium. Your health care spending account
deductions will continue from the Severance Date through December 31, 2001 at
which time your participation in the spending account plan will cease.  You will
receive documentation from Human Resources concerning distributions from the
various Millipore benefit plans in accordance with the terms of those plans.

     (4) The Company will pay you for your accrued but unused vacation up to
February 15, 2001.  You will be reimbursed for employment-related expenses
incurred prior to February 15, 2001,  in accordance with standard Millipore
procedures.  All other benefits provided to employees who are actively employed
by Millipore (other than those described in paragraphs (2) and (3) above)
terminate on the Severance Date, except that you will be able to convert your
group term life insurance coverage (excluding the accidental death and
dismemberment portion of such insurance)
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and long term disability insurance within thirty-one (31) days after your
Severance Date, in accordance with the terms of those plans.

     (5) The Company will provide up to 12 months of outplacement services
available to you, at no cost, with an outplacement firm to be determined by
Keystone Associates.

     (6) From the Severance Date until February 15, 2003, you shall not become
employed by or act as a consultant for any company or other person or
organization that competes or otherwise has business interests in conflict with
Millipore (including any subsidiary, division or affiliate) or any successor to
Millipore (including any subsidiary, division or affiliate).  Notwithstanding
the preceding sentence, Millipore will agree to your becoming employed by or
acting as a consultant to a competitor, if Millipore, in its sole discretion,
believes that you can do so without making use of or revealing any confidential
proprietary information of Millipore.  Should you wish to pursue employment with
a firm that might be covered by the non-compete terms of this Paragraph (6), you
may ask Millipore for its opinion on the matter.  We will promptly let you know
whether we believe you are precluded from working with the firm because of this
paragraph and in the event you are so precluded whether we are willing to waive
your non-compete obligation with respect to that firm.

     (7) Except for your family and legal and financial advisors, you will keep
the terms of this agreement confidential; you will not disclose to third parties
the nature or circumstances surrounding your termination of employment and you
will not speak disparagingly of Millipore, or its affiliates or successors or of
the products or business practices or management of any of them to any third
party.

     (8) You agree to hold in confidence any and all confidential and
proprietary information of Millipore to which you have had access during the
course of your employment.

     (9) You will execute the attached Agreement and Release ("Release").  (In
the event that you revoke the Release per its terms, this Agreement will be
deemed to be revoked as well.)

     B. RELOCATION PAYBACK

        The Company agrees that it will not seek reimbursement of those items
listed as "Relocation Payback" expenses in the Relocation Agreement.

     C. LOAN REPAYMENT

        Millipore agrees to withhold exercising its rights to immediate
repayment of the $450,000.00 loan provided for under the Promissory Note dated
December 9, 1999 including the documents referenced therein (the "Note") until
the date that you sell your residence in Frisco, Texas or August 14, 2001,
whichever occurs first ("Payment Date"). Should you fail to repay the principal
of the Note in full on the Payment Date, Millipore shall, at its option (a)
withhold the amount of the principal due under the Note from all severance
compensation that would otherwise be payable to you under paragraph (1) of the
Letter Agreement; or (b) liquidate the Collateral (as that term is defined in
the Note). Millipore will pay to you in one lump sum payment, the excess, if
any, of the sums collected in (a) or (b) over the principal amount due under the
Note. Except as described above, the Note shall remain in full force and effect
as per its terms.

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        The Company agrees to pay the real estate broker's fee resulting from
the sale of your residence in Frisco, Texas and confirms that you agree to pay
to the Company any appreciation in the market value of this residence in
accordance with the terms of the Relocation Agreement.

        If the above accurately reflects your understanding as to the matters
discussed above, please sign, date and return the enclosed copy of this letter
as well as the Release.  You will have 21 days from the date of this letter to
consider whether you wish to sign this letter agreement and the Release.  In
addition, you will have seven (7) days after you sign the documents to revoke
your acceptance of both.  You are encouraged to consult with an attorney with
respect to the matter of your termination and this agreement.


Very truly yours,
MILLIPORE CORPORATION


/s/ Robert Crook
----------------
Robert Crook
Manager, Human Resources
Microelectronics Division


Agreed to and accepted:


/s/ Michael P. Carroll
----------------------
Michael P. Carroll

Date:  March 28, 2001
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<PAGE>

                             AGREEMENT AND RELEASE
                             ---------------------

     Millipore Corporation (the "Company") has offered to pay me certain
severance benefits as specified in the letter dated March 20, 2001 from Robert
Crook, Manager, Human Resources, an executed copy of such letter being attached
hereto as Exhibit "A" and incorporated fully herein by reference ("Letter
Agreement"), in consideration  of my severing my employment, and waiving all
claims and releasing the Company, its affiliates and employee benefit plans and
their directors, officers, fiduciaries, employees, and agents from liability and
damages related to my employment or severance of employment.  I choose to accept
this offer.  I acknowledge and agree that my decision to accept this offer has
been made by me on a voluntary basis.  No other promise, inducement, threat,
agreement or understanding of any kind or description whatsoever has been made
with or to me by any person or entity to cause me to sign this Agreement and
Release ("Release").

     I understand that signing this Release is an important legal act.  I
acknowledge that the Company has advised me to consult an attorney before
signing this Release. I acknowledge that I have been given 21 days from the day
I receive this offer to consider this Release, and that I must sign this Release
and mail or deliver it to Robert Crook, Manager, Human Resources, Millipore
Corporation, Bedford, MA by the end of the 21st day after receipt of this offer,
for my election to receive the severance benefits specified in the Letter
Agreement. I understand that for a period of Seven (7) days following the
signing of this Release I may revoke my acceptance of the offer by either
delivering or mailing a written statement revoking my acceptance to Robert
Crook, Manager, Human Resources, Millipore Corporation, Bedford, MA and this
Release will not become effective.  In the event I revoke my acceptance of the
offer, the Letter Agreement will be deemed to be revoked as well.

     In exchange for the Company's payment to me of the severance benefits as
set forth in the Letter Agreement, I agree not to sue and I waive all claims and
release the Company, its affiliates, its employee benefit plans, their directors
and officers, fiduciaries, employees and agents (collectively, the "Released
Parties") from and against all liability and damages related in any way to my
employment with, or severance from, the Company or any of its affiliates, up
through the date of this Release.  This waiver and release includes, but is not
limited to, all claims and causes of action under Title VII of the Civil Rights
Act of 1964, as amended; the Civil Rights Act of 1991; the Age Discrimination in
Employment Act of 1967, as amended; the Civil Rights Act of 1866; the Texas
Commission on Human Rights Act; the Americans with Disabilities Act; Section 211
of the Energy Reorganization Act; the Older Workers Benefit Protection Act of
1990; the Employee Retirement Income Security Act of 1974, as amended; the
Worker Adjustment and Retraining Notification Act; the Family Medical Leave Act;
all state and federal statutes and regulations; all oral or written contract
rights, including any rights under any labor agreement as well as rights to file
a grievance; and all rights under common law such as breach of contract, tort or
personal injury of any sort.

     I understand that this Release also precludes me from recovering any relief
as a result of any lawsuit, grievance or claims brought on my behalf and arising
out of my employment or resignation of, or separation from, employment provided
that nothing in this Release will affect my entitlement, if any, to workers'
compensation or unemployment compensation.  However nothing in this Release
shall be construed as a limitation on the exercise of any and all rights I may
have to enforce the provisions of the Letter Agreement.

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     Additionally, nothing in this Release prohibits me from raising or pursuing
any safety concerns with any federal, state, or local government agency or from
cooperating in any investigation of a safety issue.  Nothing in this Release
restricts me in any way from communications with, filing a charge or complaint
with, or full cooperation in the investigations of, any governmental agency on
matters within their jurisdictions or with the Company or Company-sponsored
programs.  However, as stated above, this Release does prohibit me from
recovering any relief, including monetary relief, as a result of such
activities.

     I agree that in the course of my duties I have acquired information of a
proprietary and/or confidential nature relating to the business of the Company.
I agree to maintain in strictest confidence and not to use in any way, publish,
disclose or authorize anyone else to use, publish or disclose any proprietary,
confidential or other non-public information or document relating to the
business or affairs of the Company, its parent, or its affiliates.  I agree not
to remove or retain any figures, calculations, letters, documents, lists, papers
or copies thereof, which embody confidential and/or proprietary information of
the Company or its affiliates and to immediately return any such information in
my possession.

     I agree that should I be re-hired by Millipore while I am receiving
severance pay, my severance payments will terminate on the date of my re-
employment.

     I acknowledge that the financial, tax and similar effects of my decisions
relating to the receipt of severance will depend on my particular circumstances,
and that I should obtain advice from my own financial or tax adviser and that
none of the Released Parties are responsible for, or obligated in any way with
respect to the financial, tax or similar effects relating in any way to my
decision to receive severance or the severance received.

     If any term, provision, covenant, or restriction of this Release is held by
a court of competent jurisdiction to be invalid, void or unenforceable, the
remainder of this Release and the other terms, provisions, covenants and
restrictions hereof shall remain in full force and effect and shall in no way be
affected, impaired or invalidated.

     If timely revocation is not made, this Release shall be effective and
enforceable.  Furthermore, I understand and agree that, in the event of breach
by me of any of the terms and conditions of  the Letter Agreement and this
Release, the Company will be entitled to recover all costs and expenses as a
result of my breach.

     I HAVE READ THIS AGREEMENT AND RELEASE AND I UNDERSTAND ALL OF ITS TERMS.
I ENTER INTO AND SIGN THIS AGREEMENT AND RELEASE KNOWINGLY AND VOLUNTARILY, WITH
FULL KNOWLEDGE OF WHAT IT MEANS.

/s/ Michael P. Carroll
----------------------
Michael P. Carroll

Date: March 28, 2001
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