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                                                                   EXHIBIT 10.29

                                   AMENDMENT
                                       TO
                              EMPLOYMENT AGREEMENT

         This Amendment to Employment Contract is made this 20 day of December,
2002 by and between OM Group, Inc. ("Employer") and James P. Mooney
("Executive").

         WHEREAS, Executive and Employer, previously known as Mooney Acquisition
Corporation, entered into a certain employment agreement date September 20, 1991
(the "Agreement"); and

         WHEREAS, the Agreement was amended on one occasion; and

         WHEREAS, in order to secure the continued employment of the Executive
which the Company deems to be beneficial, the parties desire to amend the
Agreement again in certain respects;

         NOW, THEREFORE, in consideration of the mutual covenants contained
herein, the parties hereby agree the Agreement is amended, effective as of
December 1, 2002, in the following respects.

         1.     Paragraph (a) of Section 1 of the Agreement is hereby amended to
provide as follows:

                (a)   SERVICES. For the term set forth in Section 1(b),
         Executive shall serve as Chief Executive Officer of Employer. For as
         long as Executive is so employed, he shall devote his full productive
         time, energy, and abilities to his duties as Chief Executive Officer of
         the Employer, except for incidental attention to the management of his
         personal investments. Executive may serve on the board of directors of
         other corporations or organizations so long as such participation does
         not conflict with the interests or business of Employer or materially
         interfere with the performance of his duties hereunder.

         2.     Paragraph (b) of Section 1 of the Agreement is hereby amended to
provide as follows:

                (b)   TERM. The Employer agrees to continue to employ Executive
         and Executive agrees to continue to be employed by the Employer during
         the term of the Agreement, subject to the provisions hereinafter set
         forth. Unless terminated earlier as specifically provided herein, the
         revised term of the Agreement shall commence December 1, 2002, and
         continue until November 30, 2005; provided, however, that the Agreement
         shall be renewed automatically for one additional 12-month period on
         each anniversary of December 1, 2002 (an "Anniversary Date"), unless
         either the Employer or Executive gives contrary written notice at least
         six months prior an Anniversary Date. The revised term as renewed
         pursuant to the above provisions shall be 36 months as of an
         Anniversary Date.
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         3.     Paragraph (b) of Section 7 of the Agreement is hereby amended to
provide as follows:

                (b)    TERMINATION WITHOUT CAUSE. If Employer terminates
         Executive's employment without Cause, Employer shall pay Executive for
         the number of months remaining under the term of the Agreement: (i)
         100% of his current total annual monthly salary; and (ii) his "EARNED
         BONUS". Executive's earned bonus shall equal his ESTIMATED ANNUAL
         BONUS, as defined below, divided by 12 and then multiplied by the
         number of months remaining under the term of the Agreement. Executive's
         Estimated Annual Bonus shall equal the greater of (x) the average of
         Executive's annual incentive bonus paid to Executive by Employer over
         the most recent three years and (y) 75% of Executive's annual base
         salary in effect on the date of termination. Payments made under this
         Section 7(b) shall be payable during the term of the Agreement pursuant
         to the payroll practices of Employer The healthcare, life insurance,
         and nonqualified retirement benefits as well as the use of the car to
         which Executive was entitled, or was accruing, on the date of such
         termination shall be continued with respect to Executive for the period
         during which payments are made to Executive pursuant to the above
         provisions. Restricted stock granted to the Executive shall vest
         immediately in the event of Termination by Employer without cause or by
         Executive.

         4.     Paragraph (d) of Section 7 of the Agreement is hereby amended to
provide as follows:

                (d)   TERMINATION FOR DISABILITY. Employer shall have the right
         to terminate Executive's Employment on or after the date Executive
         incurs a Disability and such termination shall be treated as a
         termination without cause, except that any payments received pursuant
         to Section 7(b) shall be offset by any disability payments received
         pursuant to any disability benefit plan maintained by Employer.
         Disability for purposes of the Agreement shall mean a condition that
         renders Executive unable (as determined by Employer in good faith,
         based upon the opinion of a physician selected by Employer) to
         regularly perform his duties hereunder by reason of illness or injury
         for a period of more than six consecutive months.

         5.     Section 7 of the Agreement is hereby amended by the addition of
Paragraph (e) at the end thereof to provide as follows:

                (e)    TERMINATION BY REASON OF DEATH. In the event of
         Executive's death while in the employ of Employer, Employer shall:

                       (i) pay Executive's designated beneficiary or if there is
         no designated beneficiary, his estate, his base salary in effect on the
         date of death for the period of the term of the Agreement;

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                       (ii) pay Executive's designated beneficiary or if there
         is no designated beneficiary, his estate, his earned bonus, determined
         pursuant to the provisions of Section 7(b) for the year in which
         Executive's death occurs;

                       (iii) make, or cause to be made, such payments and
         benefits under Employer's welfare and pension plans with respect to
         Executive pursuant to the terms of such plans; and

                       (iv) restricted stock granted to the Executive shall
         vest immediately.

         6.  Section 8 of the Agreement is hereby amended to provide as follows:

              8.    RENEWAL. The Agreement shall be renewed pursuant to the
provisions of Section 1(b) above.

         IN WITNESS WHEREOF, Employer has caused this Amendment to Employment
Agreement and Executive has executed this Amendment to Employment Agreement as
of the date first above written.


OM GROUP, INC                                 EXECUTIVE

By:                                          By:
   ---------------------------------            --------------------------------
Title:


APPROVED:

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Lee R. Brodeur
Chairman, Compensation Committee


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