SIGMA ALDRICH CORP
EMPLOYMENT AGREEMENT WITH CHAIRMAN AND CEO DAVID H. HARVEY
<DOCUMENT>
<TYPE>EX-10.(G)
<SEQUENCE>3
<FILENAME>dex10g.txt
<DESCRIPTION>EMPLOYMENT AGREEMENT WITH CHAIRMAN AND CEO DAVID H. HARVEY
<TEXT>
<PAGE>

                                                                   Exhibit 10(g)

                         EXECUTIVE EMPLOYMENT AGREEMENT

          THIS EXECUTIVE EMPLOYMENT AGREEMENT ("Agreement") dated January 1,
2003 ("Effective Date") by and between the Sigma-Aldrich Corporation, a Delaware
corporation ("Company") and David Harvey ("Executive").

          WHEREAS, Executive has been effective in his service to the Company
and its subsidiaries; and

          WHEREAS, Company recognizes the valuable services that Executive has
rendered and desires to be assured that Executive will continue his active
participation in the business of the Company during management transition and
thereafter and in the event there is any change in corporate structure which
results in a Change of Control, as defined herein; and

          WHEREAS, Executive is willing to continue serving the Company and its
subsidiaries and in exchange for the protection and other consideration set
forth in this Agreement, is willing to give the Company, under certain
circumstances, his covenant not to compete.

          NOW, THEREFORE, in consideration of the promises and the mutual
agreements contained herein, the Company and Executive hereby agree as follows:


                                    ARTICLE I
                                   Definitions

1.1    Definitions. As used herein, the following terms shall have the following
       meanings.

(a)    "Affiliate" when used with reference to a Change of Control, shall be
       defined by reference to the Securities Exchange Act of 1934 and rules in
       effect thereunder as of the Effective Date of this Agreement.

(b)    "Associate" when used with reference to a Change of Control, shall be
       defined by reference to the Securities Exchange Act of 1934 and rules in
       effect thereunder as of the Effective Date of this Agreement.

(c)    "Beneficial Owner" when used with reference to a Change of Control, shall
       be defined by reference to the Securities and Exchange Act of 1934 and
       rules in effect thereunder as of the Effective Date of this Agreement.

(d)    "Board" means the board of directors of the Company.

(e)    "Cause" means (i) engaging by Executive in willful misconduct which is
       materially injurious to Company; (ii) conviction of Executive by a court
       of competent jurisdiction of, or entry of a plea of nolo contendere with
       respect to a felony; (iii) engaging by Executive in fraud, material
       dishonesty or gross misconduct in connection with the business of
       Company; (iv) engaging by Executive in any act of moral turpitude
       reasonably likely to materially and adversely affect Company or its
       business; or (v) Executive's current chronic abuse of or dependency on
       alcohol or drugs (illicit or otherwise).

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(f)    "Change of Control" occurs if any individual, corporation, partnership or
       other Person or entity, together with its Affiliates and Associates,
       acquires as the Beneficial Owner more than twenty-five percent (25%) in
       the aggregate of the outstanding shares of the Company entitled to vote
       in the election of directors, or a majority of directors elected to the
       Board, or a majority of the persons constituting a group authorized to
       hire or terminate employment of officers, if other than the Board, are
       different from the directors or persons constituting the Board or group
       just prior to the start of such period or a group other than the Board is
       created to hire or terminate employment of officers.

(g)    "Confidential Information" as used in Sections 2.5, 2.6 and 2.7 of this
       Agreement, shall mean all technical and business information of the
       Company, or which is learned or acquired by the Company from others with
       whom the Company has a business relationship in which, and as a result of
       which, similar information is revealed to the Company, whether patentable
       or not, which is of a confidential, trade secret and/or proprietary
       character and which is either developed by Executive (alone or with
       others) or to which Executive shall have had access during his
       employment. Confidential Information shall include (among other things)
       all confidential data, designs, plans, notes, memoranda, work sheets,
       formulas, processes, and Customer and supplier lists.

(h)    "Customer" means any Person or entity to whom the Company has sold any
       products (i) in the case of on-going employment, during the twenty-four
       (24) calendar months immediately preceding any dispute under Section 2.6
       of this Agreement, and, (ii) in the case of the employment having ended,
       the twenty-four (24) calendar months preceding Executive's termination of
       employment.

(i)    "Good Reason" when used with reference to a voluntary termination by
       Executive from his employment with Company, shall mean (i) a reduction in
       Executive's base salary as in effect on the date hereof, or as the same
       may be increased from time to time, during the Employment Period; (ii) a
       reduction in Executive's status, position, responsibilities or duties
       during the Employment Period; or (iii) notice of termination of this
       Agreement by the Company pursuant to Section 2.4(a), provided Executive
       terminates employment with the Company within six months of the
       expiration of the Term.

(j)    "Person" means an individual, a partnership, a corporation, an
       association, a joint stock company, a limited liability company, a trust,
       a joint venture, an unincorporated organization or a governmental entity
       or any department, agency or political subdivision thereof.

(k)    "Potential Customer" shall mean any Person or entity who, during the
       applicable twenty-four (24) month period described above in Section
       1.1(h) of this Agreement, has (i) been involved in discussions or
       negotiations with the Company for products sold by the Company; (ii)
       initiated contact with the Company in order to obtain information
       regarding products sold by the Company; (iii) been the subject of
       repeated personal contacts by Executive and/or any other Company employee
       for purposes of soliciting business for the Company; or (d) been the
       subject of the Company's efforts to gather, learn or evaluate information
       which may help the Company obtain any future order from such Person or
       entity.

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                                   ARTICLE II
                                   Employment

2.1    Employment. Company agrees to continue to employ Executive and Executive
       hereby accepts such employment with the Company, upon the terms and
       conditions set forth in this Agreement, for the period beginning on
       January 1, 2003 ("Start Date") and ending as provided in Section 2.4 of
       this Agreement (the "Employment Period").

2.2    Position and Duties.
(a)    Commencing on the Start Date and continuing during the Employment Period,
       Executive shall serve as Chief Executive Officer of the Company or in
       such other capacity as the Board may determine.

(b)    Executive shall devote his best efforts and his full business time and
       attention (except for permitted vacation periods and reasonable periods
       of illness or other incapacity) to the business and affairs of the
       Company. The Executive shall perform his duties and responsibilities to
       the best of his abilities in a diligent, trustworthy, businesslike and
       efficient manner. In the performance of his duties hereunder, Executive
       shall at all times report and be subject to the lawful direction of the
       Board and perform his duties hereunder subject to and in accordance with
       the resolutions or any other determinations of the Board and the
       certificate of incorporation and by-laws of the Company and applicable
       law. During the Employment Period, Executive shall not become an employee
       of any Person or entity other than the Company. This section shall not be
       construed to prohibit Executive from serving on the board of directors of
       one or more other entities (with the consent of the Board in the case of
       a for-profit entity) or from investing in a business to the extent
       consistent with the provisions of Section 2.6(a).

2.3    Base Salary, Bonus and Benefits.
(a)    Subject to the terms of this Agreement, in consideration of Executive's
       agreements contained herein, for the period beginning January 1, 2003,
       Executive's base salary shall be $725,000 per annum ("Base Salary"),
       which shall be payable in semi-monthly or other agreed-upon equal
       installments during the year and shall be subject to deductions for
       customary withholdings, including, without limitation, federal and state
       withholding taxes and social security taxes. Executive shall be entitled
       to the opportunity to earn annual performance bonuses (with a target
       bonus equal to 67% of base salary) in accordance with the Board-approved
       annual bonus program. In addition to the Base Salary, Executive shall be
       entitled, during the Employment Period to participate in all retirement,
       disability, pension, savings, health, medical, dental, insurance and
       other fringe benefits or plans of the Company generally available to
       executive employees.

(b)    Executive's cash compensation and bonus opportunity for 2004 and future
       years shall be reviewed and set annually by the Compensation Committee of
       the Board, but his base salary shall not be reduced below $725,000 per
       annum.

(c)    During the two-year period commencing on a Change of Control, Executive's
       Base Salary and bonus opportunity may not be reduced below the level
       established by the Compensation Committee of the Board immediately prior
       to the Change of Control.

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(d)    The Compensation Committee shall grant to the Executive 40,000 options to
       purchase Company stock (with an exercise price equal to the fair market
       value of the Company stock on the date of grant), 20,000 shares of
       restricted Company stock (subject to approval by Company stockholders),
       and a performance bonus award under which the Executive may earn up to
       $1,000,000 cash as of December 31, 2005. These awards shall be subject to
       a vesting schedule under which one-half of the value of the awards shall
       vest if the Executive is employed on December 31, 2005. All or a portion
       of the other half of the package will vest if the Executive is both
       employed on December 31, 2005 and the Company achieves performance goals
       to be established by the Board in accordance with the principles set
       forth in Section 2.3(e) below. If the Company achieves such performance
       goals in calendar years 2003, 2004, and/or 2005, 16-2/3% of the package
       will vest for each year such performance is achieved provided the
       Executive is employed on December 31, 2005. Even if the Company does not
       achieve the desired level of performance in each of 2003, 2004, and 2005,
       the other half of the package will nonetheless vest in full if the
       Executive is employed on December 31, 2005 and the Company achieves the
       desired performance for the three-year period beginning January 1, 2003
       and ending December 31, 2005. Accelerated vesting of the entire package
       shall occur in the event of Executive's employment termination prior to
       December 31, 2005 under the circumstances described in Sections
       2.4(c)(ii) or 2.4(d). A pro rata portion of the awards shall vest in the
       event of the Executive's death or disability prior to December 31, 2005.
       A pro rata portion of 50% of the awards shall vest in the event of
       Executive's involuntary termination without Cause prior to December 31,
       2005.

(e)    The performance goals used to measure vesting under Section 2.3(d) above
       will be based upon the Company's achievement of performance equal to or
       better than the average performance of its peers with respect to one or
       more or a combination of revenue growth, earnings per share growth, and
       growth in operating cashflow, as determined by the Board in its
       discretion. One possible peer group is set forth in Exhibit A to this
       Agreement. In recognition of the fact that no other business constitutes
       an exact peer to the Company, the Board may modify the peer group
       annually, or may determine that the Company's performance will be
       measured against a weighted market basket index of companies in the three
       sectors corresponding to the Company's business - life sciences, biotech
       and chemicals. These three sectors will be appropriately weighted to
       reflect the percentage of the Company's business in each such sector. In
       determining performance of the Company relative to its peers, the Board
       in its discretion shall make appropriate adjustments for acquisitions or
       divestitures, unusual or nonrecurring items which have a material effect,
       and the impact of currency adjustments.

2.4    Term.
(a)    General Term. This Agreement shall commence on the Effective Date and
       terminate on December 31, 2005 unless extended prior to that date. The
       Term shall automatically be extended for successive additional one-year
       periods unless either party to this Agreement provides the other party
       with notice of termination of this Agreement at least one hundred and
       eighty (180) days prior to the expiration of the original three-year
       period or any one-year period thereafter.

(b)    Termination for Cause or Voluntary Termination. If the Executive is
       terminated by the Company for Cause or if the Executive voluntarily
       terminates his employment in any manner except as provided in Section
       2.4(d) prior to the end of the Employment Period, the

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       Executive shall be entitled only to his Base Salary through the date of
       termination, but shall not be entitled to any further Base Salary or any
       applicable bonus or Benefits for that year or any future year, except as
       may be provided in an applicable benefit plan or program, or to any
       severance compensation of any kind, nature or amount.

(c)    Termination Without Cause.
       (i)   Before or More Than Twenty-Four Months Following Change of Control.
             If the Executive is involuntarily terminated by the Company prior
             to the end of the Employment Period without Cause before a Change
             in Control (excluding any involuntary termination which is a direct
             result of a Change in Control and which occurs within 60 days
             before a Change in Control) or more than twenty-four months
             following a Change of Control, the Executive shall be entitled to
             all previously earned and accrued but unpaid Base Salary up to the
             date of such termination and severance pay equal to one year of
             Base Salary. Such severance payments will be made in equal
             installments over a one-year period payable on the dates on which
             the Executive's Base Salary would have otherwise been paid if
             Executive's employment had continued. All payments shall be subject
             to deductions for customary withholdings, including, without
             limitation, federal and state withholding taxes and social security
             taxes.

       (ii)  Within Twenty-Four Months After Change of Control. If the Executive
             is involuntarily terminated by the Company without Cause prior to
             the end of the Employment Period within twenty-four months after a
             Change of Control or within 60 days before a Change in Control if
             such involuntary termination without Cause is a direct result of
             the Change in Control, the Executive shall be entitled to all
             previously earned and accrued but unpaid Base Salary up to the date
             of such termination and severance pay equal to three (3) years of
             Base Salary. Such severance payments will be made in equal
             installments over a three-year period payable on the dates on which
             the Executive's Base Salary would have otherwise been paid if
             Executive's employment had continued. All payments shall be subject
             to deductions for customary withholdings, including, without
             limitation, federal and state withholding taxes and social security
             taxes.

(d)    Voluntary Termination for Good Reason. If Executive voluntarily
       terminates his employment for Good Reason within twenty-four (24) months
       after a Change of Control, Executive shall notify Company in writing if
       he believes the termination is for Good Reason. Executive shall set forth
       in reasonable detail why Executive believes Good Reason exists. If such
       termination is determined to be for Good Reason, Executive shall be
       entitled to all previously earned and accrued but unpaid Base Salary up
       to the date of such termination and severance pay equal to three (3)
       years of Base Salary. Such severance payments will be made in equal
       installments over a three-year period payable on the dates on which the
       Executive's Base Salary would have otherwise been paid if Executive's
       employment had continued. All payments shall be subject to deductions for
       customary withholdings, including, without limitation, federal and state
       withholding taxes and social security taxes.

(e)    No Mitigation. To the extent that Executive shall receive compensation
       for personal services from employment other than with the Company
       subsequent to a termination of Executive's employment with the Company,
       the amounts so earned shall not be offset

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       against the amounts (if any) due under this Agreement following
       Executive's termination of employment.

(f)    Limitation on Certain Additional Payments. Anything in this Agreement to
       the contrary notwithstanding, in the event it shall be determined that
       any payment or distribution by Company to or for the benefit of Executive
       ("Payments") would be subject to the excise tax imposed by Section 4999
       of the Internal Revenue Code of 1986, as amended ("Code"), then the
       Payments due under this Agreement shall be decreased to the greatest
       amount that could be paid to Executive such that receipt of Payments
       would not give rise to any such excise tax.

(g)    Severance Forfeiture. Executive agrees that the Executive shall be
       entitled to the severance pay as set forth in this Section 2.4 only if
       the Executive has not materially breached as of the date of termination
       any provisions of this Agreement and does not materially breach such
       provisions at any time during the period for which such payments are to
       be made. The Company's obligation to make such payments will terminate
       upon the occurrence of any such material breach during the severance
       period.

(h)    No Additional Severance. Executive hereby agrees that no severance
       compensation of any kind, nature or amount shall be payable to Executive,
       except as expressly set forth in this Section 2.4, and Executive hereby
       irrevocably waives any claim for any other severance compensation.

(i)    Death or Disability. The Company's obligation under this Agreement
       terminates on the last day of the month in which the Executive's death
       occurs or on the date as of which Executive first becomes entitled to
       receive disability benefits under the Company's long-term disability
       plan. The Company shall pay to Executive or the Executive's estate all
       previously earned and accrued but unpaid Base Salary up to such date.
       Thereafter, the Executive or his estate shall not be entitled to any
       further Base Salary, bonus or Benefits for that year or any subsequent
       year, except as may be provided in an applicable benefit plan or program.

2.5    Confidential Information.
(a)    Executive recognizes that the Company is engaged in the business of
       research, development, manufacture and sale of chemicals, chemical
       products and allied activities throughout the world (the "Company's
       Business"), which business requires for its successful operation the
       fullest security of its Confidential Information of which Executive will
       acquire knowledge during the course of his employment.

(b)    Executive shall use his best efforts and diligence both during and after
       his employment with the Company, regardless of how, when or why
       Executive's employment ends, to protect the confidential, trade secret
       and/or proprietary character of all Confidential Information. Executive
       shall not, directly or indirectly, use (for himself or another) or
       disclose any Confidential Information, for so long as it shall remain
       proprietary or protectible as confidential or trade secret information,
       except as may be necessary for the performance of Executive's duties for
       the Company.

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(c)    Executive shall promptly deliver to the Company, at the termination of
       the Employment Period or at any other time at the Company's request,
       without retaining any copies, all documents, information and other
       material in Executive's possession or control containing, reflecting
       and/or relating, directly or indirectly, to any Confidential Information.

(d)    Executive's obligations under this Section 2.5 shall also extend to the
       confidential, trade secret and proprietary information learned or
       acquired by Executive during his employment from others with whom the
       Company has a business relationship.

(e)    Executive's breach of Section 2.5 of this Agreement shall relieve Company
       of its obligations (if any) to pay any further severance benefits under
       this Agreement.

2.6    Competitive Activity.
(a)    Executive shall not, directly or indirectly (whether as owner, partner,
       consultant, employee or otherwise), at any time during his employment
       with the Company and for a period of two (2) years following his
       employment with the Company, regardless of how, when or why Executive's
       employment terminates, (i) engage in or invest in any business that is
       engaged in any work or activity that involves a product, process, service
       or development which is then competitive with and the same as or similar
       to a product, process, service or development on which Executive worked
       or with respect to which Executive had access to Confidential Information
       while with the Company, or (ii) otherwise compete against the Company's
       Business.

(b)    Following expiration of the two-year period in Section 2.6(a) of this
       Agreement, Executive shall continue to be obligated under Section 2.5 of
       this Agreement not to use or to disclose Confidential Information so long
       as it shall remain proprietary or protectible as confidential or trade
       secret information.

(c)    Following termination of Executive's employment with the Company for any
       reason, Executive agrees to advise the Company of his new employer, work
       location and job responsibilities within three (3) days after accepting
       new employment if such new employment commences within two (2) years
       following Executive's termination of employment with the Company.
       Executive further agrees to keep the Company so advised of any change in
       his employment for two (2) years following the termination of his
       employment with the Company.

(d)    Executive understands that the intention of Sections 2.5 and 2.6 of this
       Agreement is not to prevent the Executive from earning a livelihood and
       Executive agrees nothing in this Agreement would prevent Executive from
       earning a livelihood utilizing his general purchasing, sales,
       professional or technical skills in any of the hospitals, businesses,
       research or manufacturing facilities of companies which are not directly
       or indirectly in competition with the Company.

(e)    Executive agrees that during his employment with the Company and for a
       period of two (2) years following Executive's termination of employment,
       regardless of how, when or why employment ceased, Executive shall not in
       any manner or in any capacity, directly or indirectly, for himself or any
       other Person or entity, actually or attempt to: (i) solicit any Customer
       or Potential Customer of the Company for the purpose of selling any
       products

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       competitive with products sold by the Company, or otherwise interfere
       with or take away any Customer or Potential Customer of the Company or
       the business of any such Customer or Potential Customer; or (ii)
       interfere with the Company's relationship with any Customer or supplier
       of the Company.

(f)    During Executive's employment with the Company and for a period of two
       (2) years following Executive's termination of employment, regardless of
       how, why or when employment ceased, Executive shall not, directly or
       indirectly, solicit for employment, hire or offer employment to, or
       otherwise aid or assist (by disclosing information about employees or
       otherwise) any other person or entity other than the Company in
       soliciting for employment, hiring or offering employment to, any employee
       of the Company.

(g)    Executive's breach of Section 2.6 of this Agreement shall relieve Company
       of its obligations (if any) to pay any further severance benefits under
       this Agreement.

2.7    Ideas, Inventions and Discoveries.
(a)    Executive shall promptly disclose to the Company any ideas, inventions or
       discoveries, whether or not patentable, which Executive may conceive or
       make (alone or with others) during the Employment Period, whether or not
       during working hours, and which, directly or indirectly (i) relate to
       matters within the scope of Executive's duties or field of responsibility
       during Executive's employment with the Company; or (ii) are based on
       Executive's knowledge of the actual or anticipated business or interest
       of the Company; or (iii) are aided by the use of time, materials,
       facilities or information of the Company.

(b)    Executive hereby assigns to the Company or its designee, without further
       compensation, all of the right, title and interest in all such ideas,
       inventions or discoveries in all countries of the world except for
       patents currently held by Executive developed outside of employment with
       the Company.

(c)    Without further compensation but at the Company's expense, Executive
       shall give all testimony and execute all patent applications, rights of
       priority, assignments and other documents and in general do all lawful
       things requested of Executive by the Company to enable the Company to
       obtain, maintain and enforce protection of such ideas, inventions and
       discoveries for and in the name of the Company or its designee, as the
       case may be, in all countries of the world. However, should Executive
       render any of the services in this Section 2.7(c) during a two-year
       period following termination of Executive's employment, Executive shall
       be compensated at a rate per hour equal to the base salary Executive
       received from the Company at the time of termination and shall be
       reimbursed for reasonable out-of-pocket expenses incurred in rendering
       the services.

(d)    Executive's breach of Section 2.7 of this Agreement shall relieve Company
       of its obligations (if any) to pay any further severance benefits under
       this Agreement.

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                                   ARTICLE III
                                  Miscellaneous

3.1    Executive's Representations. Employee hereby represents and warrants to
the Company that (i) Executive's execution, delivery and performance of this
Agreement do not and shall not conflict with, breach, violate or cause a default
under any contract, agreement, instrument, order, judgment or decree to which
Executive is a party or by which he is bound, (ii) Executive is not a party to
or bound by any employment agreement, noncompete agreement or confidentiality
agreement with any other person or entity and (iii) upon the execution and
delivery of this Agreement by the Company, this Agreement shall be the valid and
binding obligation of Executive, enforceable in accordance with its terms.
Executive hereby acknowledges and represents that he fully understands the terms
and conditions contained herein.

3.2    Survival. Sections 2.5, 2.6 and 2.7 and Sections 3.3 through 3.12 shall
survive and continue in full force in accordance with their terms
notwithstanding any termination of the Employment Period.

3.3    Notices. All notices, demands or other communications to be given or
delivered under or by reason of the provisions of this Agreement will be in
writing and will be deemed to have been given when delivered personally, mailed
by certified or registered mail, return receipt requested and postage prepaid,
or sent via a nationally recognized overnight courier, or sent via facsimile to
the recipient. Such notices, demands and other communications will be sent to
the address indicated below:

          To the Company:
                   Mr. Kirk Richter
                   Sigma-Aldrich Corporation
                   3050 Spruce
                   St. Louis, MO 63103

          To Executive:
                   Mr. David Harvey
                   1470 East Bay Point Road
                   Whitefish Bay, Wisconsin 53217

          With a copy to:
                   Mr. Joseph T. Porter, Jr.
                   Polsinelli Shalton Welte
                   100 South Fourth Street, Suite 1100
                   St. Louis, MO 63102


or such other address or to the attention of such other person as the recipient
party shall have specified by prior written notice to the sending party.

3.4    Severability. Whenever possible, each provision of this Agreement will be
interpreted in such manner as to be effective and valid under applicable law. If
any provision of this Agreement is held to be invalid, illegal or unenforceable
in any respect under any applicable law or rule in any

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jurisdiction, (a) the parties agree that such provision(s) will be enforced to
the maximum extent permissible under the applicable law, and (b) any invalidity,
illegality or unenforceability of a particular provision will not affect any
other provision of this Agreement.

3.5    Successors and Assigns. Except as otherwise provided herein, all
covenants and agreements contained in this Agreement shall bind and inure to the
benefit of and be enforceable by the Company, and their respective successors
and assigns. This Agreement is personal to Executive and except as otherwise
specifically provided herein, this Agreement, including the obligations and
benefits hereunder, may not be assigned to any party by Executive.

3.6    Descriptive Headings. The descriptive headings of this Agreement are
inserted for convenience only and do not constitute a part of this Agreement.

3.7    Counterparts. This Agreement may be executed in one or more identical
counterparts, each of which shall be deemed an original but all of which
together shall constitute one and the same instrument.

3.8    Waiver. Neither any course of dealing nor any failure or neglect of
either party hereto in any instance to exercise any right, power or privilege
hereunder or under law shall constitute a waiver of such right, power or
privilege or of any other right, power or privilege or of the same right, power
or privilege in any other instance. Without limiting the generality of the
foregoing, Executive's continued employment without objection shall not
constitute Executive's consent to, or a waiver of Executive's rights with
respect to, any circumstances constituting Good Reason. All waivers by either
party hereto must be contained in a written instrument signed by the party to be
charged therewith, and, in the case of Company, by its duly authorized officer.

3.9    Entire Agreement. This instrument constitutes the entire agreement of the
parties in this matter and shall supersede any other agreement between the
parties, oral or written, concerning the same subject matter including, but not
limited to, any prior employment and severance agreements, including the
Employment Agreement executed by the parties on May 1, 1984 and the agreement
regarding confidential information and competitive activities executed by the
parties on August 30, 1982.

3.10   Amendment. This Agreement may be amended only by a writing which makes
express reference to this Agreement as the subject of such amendment and which
is signed by Executive and by a duly authorized officer of the Company.

3.11   Governing Law. This Agreement shall be signed by the parties in St.
Louis, Missouri. All questions concerning the construction, validity and
interpretation of this Agreement and exhibits and schedules hereto will be
governed by and construed in accordance with the domestic law of the State of
Missouri, without giving effect to any choice of law or conflict of law
provision or rule (whether of the State of Missouri or any other jurisdiction)
that would cause the application of the laws of any jurisdiction other than the
State of Missouri. Any litigation relating to or arising out of this Agreement
shall be filed and litigated exclusively in the St. Louis County Circuit Court
or the United States District Court for the Eastern District of Missouri.

3.12   Remedies. Each of the parties to this Agreement will be entitled to
enforce its rights under this Agreement specifically, to recover damages and
costs (including reasonable attorneys' fees)

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caused by any breach of any provision of this Agreement and to exercise all
other rights existing in its favor. The parties hereto agree and acknowledge
that money damages may not be an adequate remedy for any breach of the
provisions of this Agreement, including, without limitation, Sections 2.5, 2.6
and 2.7 hereof, and that any party may in its sole discretion apply to any court
of law or equity of competent jurisdiction (without posting any bond or deposit)
for specific performance and/or other injunctive relief in order to enforce or
prevent any violations of the provisions of this Agreement.

3.13   Exit Interview. To ensure a clear understanding of this Agreement,
Executive agrees, at the time of termination of Employee's employment, to engage
in an exit interview with the Company at a time and place designated by the
Company and at the Company's expense. Executive understands and agrees that
during said exit interview, Executive may be required to confirm that he will
comply with his on-going obligations under this Agreement. The Company may
elect, at its option, to conduct the exit interview by telephone.

3.14   Future Employment. Executive shall disclose the existence of this
Agreement to any new employer or potential new employer which offers products or
services that compete with the Company's Business if such new employment
commences within two (2) years following Executive's termination of employment
with the Company. Executive consents to the Company informing any subsequent
employer of Executive, or any entity which the Company in good faith believes
is, or is likely to be, considering employing Executive, of the existence and
terms of this Agreement if such subsequent employment commences (or is expected
to commence) within two (2) years following the Executive's termination of
employment with the Company.

          IN WITNESS WHEREOF, the parties hereto have executed this Employment
Agreement as of the date first written above.

                                        SIGMA-ALDRICH CORPORATION


                                        By:   /s/ Kirk Richter
                                            ------------------

                                        Name: Kirk Richter

                                        Title: Treasurer


                                        EXECUTIVE


                                        By:   /s/ David Harvey
                                            ------------------
                                        Name: David Harvey

                                       11

<PAGE>

                                    EXHIBIT A

                               INITIAL PEER GROUP

Apogent Technologies, Inc.
Applied Biosystems Group
Fisher Scientific International, Inc.
Invitrogen Corporation
Waters Corporation

                                       12

</TEXT>
</DOCUMENT>
