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                                                                   Exhibit 10.14
                   AMENDED & RESTATED EMPLOYMENT AGREEMENT

EMPLOYMENT AGREEMENT dated December 15, 1995 (the "Employment Agreement") by and
between MKS Instruments, Inc., a Massachusetts Corporation (the "Corporation"),
and Gerald Colella of Lowell, MA (the "Employee").

WHEREAS, the Corporation and the Employee entered into an Employment Agreement
dated February 28, 1994 (the "Original Employment Agreement"); and

WHEREAS, the Corporation has adopted a new Management Incentive Program and the
Employee desires to be eligible to participate in such Management Incentive
Program; and

WHEREAS, the Corporation and the Employee desire to make certain other
amendments to the Original employment Agreement as more particularly set forth
herein; and

WHEREAS, for convenience of reference, the Corporation and the Employee desire
to amend and restate the Original Employment Agreement in its entirety:

NOW, THEREFORE, in consideration of the premises and the mutual promises
contained herein, and for other good and valuable considerations, the receipt
and sufficiency of which are hereby acknowledged, The Corporation and the
Employee hereby agree that the Original Employment Agreement is hereby amended
and restated to read in its entirety as follows:

      (1) Term of Employment: The Corporation hereby employs the Employee, and
the Employee hereby accepts employment with the Corporation, for a period
commencing as of December 15, 1995 and continuing from month to month thereafter
until terminated as provided in this Section (1). Either the Corporation or the
Employee may terminate the employment of the Employee under this Employment
Agreement at any time after December 15, 1995 by giving written notice to the
other party stating its or his election to terminate the employment of the
Employee under this Employment Agreement. The employment of the Employee under
this Employment Agreement shall terminate thirty (30) days after the date of
receipt by the other party of such notice; provided, however, that the
employment of the Employee under this Employment Agreement is subject to prior
termination as hereinafter provided in Section (5).

      (2) Capacity: The Employee shall serve in such capacity as may be assigned
to him consistent with his training and experience for the term of employment
under this Employment Agreement and shall have such authority as is delegated to
him by the President of the Corporation, or his designee.

      (3) Extent of Services: During the term of employment of the Employee
under this
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Employment Agreement, the Employee shall devote his full time to, and use his
best efforts in the furtherance of, the business of the Corporation and shall
not engage in any other business activity, whether or not such business activity
is pursued for gain or any other pecuniary advantage, without the prior written
consent of the Corporation.

      (4) Compensation: In consideration of the services to be rendered by the
Employee under this Employment Agreement, the Corporation agrees to pay, and the
Employee agrees to accept, the following compensation:

            (a) Base Salary: A base salary at the rate of $110,000 per year for
the term of employment of the Employee under this Employment Agreement. The base
salary shall be payable in equal weekly, biweekly, or bimonthly installments
subject to usual withholding requirements. Base salary will be reviewed
according to the established practices of the corporation. No overtime pay will
be paid to the Employee by the Corporation.

            (b) Incentive: For each calendar year of the Corporation during the
term of employment of the Employee under this Employment Agreement, the Employee
shall be entitled to participate in a Management Incentive Program pursuant to
the terms of which the Employee may receive compensation in addition to his base
salary in an amount equal to a specified percentage of his base salary if the
Corporation attains its consolidated financial goals during such calendar year
of the Corporation. The Management Incentive Program, including the consolidated
financial goals established by the Corporation for the calendar year and the
formula to be used to determine the payment of amounts under the Management
Incentive Program, will be communicated to the Employee in writing prior to the
beginning of each calendar year of the Corporation. The first calendar year of
the Corporation for purposes of the Management Incentive Program will commence
on January 1, 1996 and end on December 31, 1996. If the term of employment of
the Employee under this Employment Agreement shall include a portion of a
calendar year of the Corporation commencing after January 1, 1996, the
Corporation shall not pay the Employee, and the Employee shall not be entitled
to receive, any amount under the Management Incentive Program.

            If there shall be any disagreement between the Corporation and the
Employee as to the calculation of the Management Incentive Bonus in any calendar
year of the Corporation during the term of employment of the Employee under this
Employ- ment Agreement, the decision of the independent Public Accounting firm
of the Cor-poration as to the amount of the Management Incentive Bonus of the
Corporation shall be conclusive and binding on the Corporation and the Employee.
The Employee shall have no right to inspect any of the books, papers or records
of the Corporation, except that the Employee shall be entitled to inspect any
certificate of such independent public of the Corporation in any calendar year
of the Corporation during the term of employment of the Employee under this
Employment Agreement.



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            Incentive payments shall be payable to the Employee on or before
March 31 after the end of each calendar year of the Corporation during the term
of employment of the Employee under this Employment Agreement.

            (c) MKS Instruments, Inc. Profit Sharing and Retirement
                Savings Plan: The Employee shall be eligible to participate in
the the MKS Instruments, Inc. Profit Sharing and Retirement Savings Plan upon
satisfaction of the conditions set forth therein.

            (d) Vacation: The Employee shall be entitled to an annual vacation
leave of 18 days at full pay during each calendar year during the term of
employment of the Employee under this Employment Agreement, subject to the
Employee arranging such vacation so as not to affect adversely the ability of
the Corporation to transact its necessary business.

            (e) Life Insurance: The Corporation shall provide, and pay all of
the premiums for, term life insurance for the Employee during the term of
employment of the Employee under this Employment Agreement in accordance with
the term life insurance plan of the Corporation.

            (f) Medical/Dental Insurance: The Corporation shall provide group
medical/dental insurance for the Employee under the Plans of the Corporation
applicable to the Employee during the term of employment of the Employee under
this Employment Agreement.

            (g) Other Benefits: The Corporation shall provide other benefits for
the employee under the Plans of the Corporation applicable to the Employee
during the term of employment of the Employee under this Employment Agreement.

      (5) Termination: The employment of the Employee under this Employment
Agreement shall terminate:


            (a) On the expiration of the period of employment as provided in
Section (1).

            (b) Upon the death of the Employee.

            (c) At the election of the Corporation (i) if the Employee shall
fail, or refuse, to perform the services required of him under this Employment
Agreement, or (ii) if the Employee shall fail, or refuse, to perform the other
covenants and agreements required of him under this Employment Agreement, or
(iii) for "cause", which term shall mean acts or actions detrimental to the best
interests of the Corporation.



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      (6) Payment Upon Termination:


            (a) If the employment of the Employee is terminated on the
expiration of the period of employment as provided in Section (1), the Employee
shall not be entitled to any compensation, and the Corporation shall have no
obligation to pay the Employee any compensation, except as is provided in this
Employment Agreement.

            (b) If the employment of the Employee is terminated by death, the
Corporation shall pay to the estate of the Employee the compensation which would
otherwise be payable to the Employee at the end of the month in which his death
occurs.

            (c) In the event the employment of the Employee is terminated at the
election of the Corporation pursuant to Section (5) (c) hereof, the Employee
shall only be entitled to his base salary through the last day of actual
employment or the date of termination, whichever is earlier.

      (7) Trade Secrets: The Employee covenants and agrees that he will
communicate to the Corporation, and will not divulge or communicate to any other
person, partnership, corporation or other entity without the prior written
consent of the Corporation, any trade secrets of the Corporation or confidential
information relating to the business of the Corporation or any one connected
with the Corporation, and that such trade secrets and confidential information
shall not be used by the Employee either on his own behalf or for the benefit of
others or disclosed by the Employee to any one, except to the Corporation,
during or after the term of employment of the Employee under this Employment
Agreement. "Trade secrets of the Corporation" shall include, but not be limited
to, Inventions, trade secrets, files, records, drawings, specifications,
processes, lists of material, lists of customers, sales and marketing
strategies, product development plans, financial information, and information on
research and development.

      (8) Inventions and Patents:


            (a) The Employee shall make prompt full disclosure in writing to the
Corporation of all inventions, improvements and discoveries, whether or not
patentable, which the Employee conceives, devises, makes, discovers, develops,
perfects or first reduces to practice, either alone or jointly with others,
during the term of employment of the Employee under this Employment Agreement,
which relate in any way to the fields, products or business of the Corporation,
including development and research, whether during or out of the usual hours of
work or on or off the premises of the Corporation or by use of the facilities of
the Corporation or otherwise and whether at the request or suggestion of the
Corporation or otherwise (all such inventions, improvements and discoveries
being hereinafter called the "Inventions"), including any Inventions, whether or
not patentable, conceived, devised, made, discovered, developed, perfected or
first reduced to practice by the Employee after the



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employment of the Employee under this Employment Agreement is terminated if the
Inventions were conceived by the Employee during the term of employment of the
Employee under this Employment Agreement. Any Inventions, whether or not
patentable, conceived, devised, made, discovered, developed, perfected or first
reduced to practice by the Employee within six (6) months of the date of
termination of the employment of the Employee under this Employment Agreement
shall be conclusively presumed to have been conceived during the term of
employment of the Employee under this Employment Agreement.

            (b) The Employee agrees that the Inventions shall be the sole and
exclusive property of the Corporation.

            (c) The Employee agrees to assist the Corporation and its nominees
in every reasonable way (entirely at its or their expense) to obtain for the
benefit of the Corporation letters patent for the Inventions and trademarks,
trade names and copyrights relating to the Inventions, and any renewals,
extensions or reissues thereof, in any and all countries, and agrees to make,
execute, acknowledge and deliver, at the request of the Corporation, all written
applications for letters patent, trademarks, trade names and copyrights relating
to the Inventions and any renewals, extensions or reissues thereof, in any and
all countries, and all documents with respect thereto, and all powers of
attorney relating thereto and, without further compensation, to assign to the
Corporation or its nominees all the right, title and interest of the Employee in
and to such applications and to any patents, trademarks, trade names or
copyrights which shall thereafter issue on any such applications, and to
execute, acknowledge and deliver all other documents deemed necessary by the
Corporation to transfer to or vest in the Corporation all of the right, title
and interest of the Employee in and to the Inventions, and to such trademarks,
trade names, patents and copyrights together with exclusive rights to make, use,
license and sell them throughout the world.

            (d) The Employee agrees that even though his employment is
terminated under this Employment Agreement he will, at any time after such
termination of employment, carry out and perform all of the agreements of
Subsections (8) (a) and (8) (c) above, and will at any time and at all times
cooperate with the Corporation in the prosecution and/or defense of any
litigation which may arise in connection with the Inventions, provided, however,
that should such services be rendered after termination of employment of the
Employee under this Employment Agreement, the Employee shall be paid reasonable
compensation on a per diem basis.

            (e) The Employee agrees to make and maintain adequate and current
written records of all Inventions in the form of notes, sketches, drawings, or
reports relating thereto, which records shall be and remain the property of, and
available to, the Corporation at all times.

            (f) The Employee agrees that he will, upon leaving the employment of
the Corporation, promptly deliver to the Corporation all originals and copies of
disclosures, drawings, prints, letters, notes, and reports either typed,
handwritten or otherwise memorialized, belonging to the Corporation which are in
his possession or



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under his control and the Employee agrees that he will not retain or give away
or make copies of the originals or copies of any such disclosures, drawings,
prints, letters, notes or reports.

      (9) Property of Corporation: All files, records, reports, documents,
drawings, specifications, equipment, and similar items relating to the business
of the Corporation, whether prepared by the Employee or otherwise coming into
his possession, shall remain the exclusive property of the Corporation and shall
not be removed by the Employee from the premises of the Corporation under any
circumstances whatsoever without the prior written consent of the Corporation.

      (10) Non-Competition:


            (a) In order to protect the good will of the Corporation and in
order to protect the trade secrets of the Corporation referred to in Section (7)
of this Employment Agreement, the Employee hereby agrees that during the term of
employment of the Employee under this Employment Agreement, and during a period
of one (1) year after termination of employment of the Employee under this
Employment Agreement without regard to the cause of termination of employment
and whether or not such termination of employment was caused by the Employee or
by the Corporation, (i) the Employee shall not engage, either directly or
indirectly, in any manner or capacity, in any business or activity which is
competitive with any business or activity conducted by the Corporation; (ii) the
Employee shall not work for or employ, directly or indirectly, or cause to be
employed by another, any person who was an employee, officer or agent of the
Corporation or of any of its subsidiaries at any time during a period of twelve
(12) months prior to the termination of the employment of the Employee under
this Employment Agreement, provided such employment is competitive with any
business or activity of the Corporation, nor shall the Employee form any
partnership with, or establish any business venture in cooperation with, any
such person which is competitive with any business or activity of the
Corporation; (iii) the Employee shall not give, sell or lease any goods or
services competitive with the goods or services of the Corporation or its
subsidiaries to any person, partnership, corporation or other entity who
purchased goods or services from the Corporation or its subsidiaries within one
(1) year before the termination of the employment of the Employee under this
Employment Agreement; (iv) the Employee shall not participate as a director,
officer, partner, employee, consultant or otherwise, in any corporation,
partnership or other entity which is competitive with any business or activity
conducted by the Corporation.

            (b) The Corporation and the Employee agree that the services of the
Employee are of a personal, special, unique and extraordinary character, and
cannot be replaced by the Corporation without great difficulty, and that the
violation by the Employee of any of his agreements under this Section (10) would
damage the goodwill of the Corporation and cause the Corporation irreparable
harm which could not reasonably or adequately be compensated in damages in an
action at law, and that the agreements of the Employee under this Section (10)
may be enforced by the Corporation in equity by an injunction or restraining
order in addition to being enforced by the Corporation at law.



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            (c) In the event that this Section (10) shall be determined by any
court of competent jurisdiction to be unenforceable by reason of its extending
for too long a period of time or over too great a range of activities, it shall
be interpreted to extend only over the maximum period of time or range of
activities as to which it may be enforceable.

      (11) Notice: Any and all notices under this Employment Agreement shall be
in writing and, if to the Corporation, shall be duly given if sent to the
Corporation by registered or certified mail, postage prepaid, return receipt
requested, at the address of the Corporation set forth under its name below or
at such other address as the Corporation may hereafter designate to the Employee
in writing for the purpose, and if to the Employee, shall be duly given if
delivered to the Employee by hand or if sent to the Employee by registered or
certified mail, postage prepaid, return receipt requested, at the address of the
Employee set forth under his name below or at such other address as the Employee
may hereafter designate to the Corporation in writing for the purpose.

      (12) Assignment: The rights and obligations of the Corporation under this
Employment Agreement shall inure to the benefit of, and shall be binding upon,
the successors and assigns of the Corporation. The rights and obligations of the
Employee under this Employment Agreement shall inure to the benefit of, and
shall be binding upon, the heirs, executors and legal representatives of the
Employee.

      (13) Entire Agreement and Severability:

            (a) This Employment Agreement supersedes any and all other
agreements, either oral or in writing, between the parties hereto with respect
to the employment of the Employee by the Corporation and contains all of the
covenants and agreements between the parties with respect to such employment.
Each party to this Employment Agreement acknowledges that no representations,
inducements, promises or agreements, oral or otherwise, have been made by any
party, or any one acting on behalf of any party, which are not embodied herein,
and that no other agreement, statement or promise not contained in this
Employment Agreement shall be valid and binding. Any modification of this
Employment Agreement will be effective only if it is in writing signed by both
parties to this Employment Agreement.

            (b) If any provision in this Employment Agreement is held by a court
of competent jurisdiction to be invalid, void or unenforceable, the remaining
provisions shall nevertheless continue in full force and effect without being
impaired or invalidated in any way.

            (c) All pronouns used herein shall include the masculine, feminine,
and neuter gender as the context requires.

      (14) Governing Law and Jurisdictions: This Employment Agreement shall be
governed by, and construed in accordance with, the laws of The Commonwealth of
Massachusetts applicable to contracts made and to be performed entirely within
The



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Commonwealth of Massachusetts (without reference to conflict of laws
principles). Any action or proceeding arising from or in connection with this
Employment Agreement may be brought against the Employee in a court of record of
The Commonwealth of Massachusetts, Middlesex County, or in the United States
District Court for the District of Massachusetts, the Employee hereby consenting
to the jurisdiction thereof over its person; and service of process may be made
upon the Employee by mailing a copy of the summons and any complaint to the
Employee by registered or certified mail, postage prepaid, return receipt
requested, at the address to be used for the giving of notice to the Employee as
provided in this Employment Agreement.

IN WITNESS WHEREOF, the parties hereto have executed this Employment Agreement
as a sealed instrument in the Commonwealth of Massachusetts, all as of the day,
month and year first written above.

                                    MKS INSTRUMENTS, INC.

                                    By:  /s/ John R. Bertucci
                                         ---------------------------------
                                         John R. Bertucci, President

                                         Six Shattuck Road
                                         Andover, MA  01810

                                         /s/ Gerald Colella
                                         ---------------------------------
                                         Employee Signature

                                         Gerald Colella
                                         ---------------------------------
                                         Employee Name

                                         Address:
                                         61 Heritage Drive
                                         ---------------------------------
                                         Lowell, MA 01852
                                         ---------------------------------


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