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                                                                  Exhibit 10.42


                              EMPLOYMENT AGREEMENT
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        This Employment Agreement (the "Agreement") is made as of December 18,
1995 by and between OM Group, Inc., a Delaware corporation ("Employer"), and
Terry L. Guckes of Cleveland, Ohio ("Executive").

        WHEREAS, Employer and Executive desire to enter into this Agreement to
provide for Executive's continued employment with Employer.

        NOW, THEREFORE, in consideration of the mutual covenants contained
herein and other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the parties hereto agree as follows:

        1. EMPLOYMENT. Employer agrees to employ Executive and Executive accepts
such continued employment upon the terms and subject to the conditions set forth
in this Agreement.

           (A) SERVICES. For the term set forth in Section 1(b), Executive shall
serve as Vice President Planning & Development(1) and shall render such services
of an executive and administrative character as Employer specifies. For as long
as Executive is so employed, he shall devote his full productive time, energy
and ability to his duties, except for incidental attention to the management of
his personal investments. Executive may serve on the board of directors of other
companies or organizations so long as such participation does not conflict with
the interests or business of Employer or its subsidiaries or materially
interfere with the performance of his duties hereunder.

           (B) TERM. Unless earlier terminated pursuant to the provisions of
Section 7, the Initial Term of this Agreement shall commence on the date hereof
and shall expire on December 31, 1996. If the Initial Term has been renewed
pursuant to the provisions of Section 8 (the "Renewal Term"), the term of this
Agreement shall extend through the expiration of any Renewal Term then in
effect, unless earlier terminated pursuant to the provisions of Section 7. All
references herein to the "term of this Agreement" shall be deemed to refer to
the Initial Term as well as any Renewal Term then in effect if the Initial Term
has been extended pursuant to Section 8.

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(1)   Subject to Board approval at February 6, 1996 meeting.

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           (B) AGREEMENT AS TO SCOPE. If, at the time of enforcement of any
provision of Section 2(A), a court of competent jurisdiction holds that the
restrictions stated therein are unreasonable under circumstances then existing,
the parties agree that the maximum period, scope, or geographical area
reasonable under such circumstances shall be substituted for the period, scope,
or geographical area stated therein.

        3. NON-SOLICITATION. Executive agrees that, during the term of this
Agreement and for a period of (1) year thereafter, he will not knowingly, either
directly or indirectly, for himself or for any other person or entity, divert,
call on, solicit, or take away, or attempt to divert, call on, solicit, or take
away present or actively solicited prospective employees or, with respect to
competitive products or services, any present or actively solicited prospective
suppliers (including, without limitation, cobalt suppliers) or customers of
Employer, or any of its controlled subsidiaries.

        4. CONFIDENTIAL INFORMATION. Executive acknowledges that during the
course of his employment under this Agreement he will make use of, acquire and
add to confidential information of a special and unique nature and value
relating to such matters as trade secrets, systems, procedures, manuals,
confidential reports and lists of suppliers, customers and other business
contacts of Employer and its subsidiaries, as well as the nature and type of
services rendered to such persons. Executive agrees that he will not disclose to
an unauthorized person or use for his own account any of such information
without the prior written consent of the Board of Directors of Employer, unless
and to the extent that the aforementioned matters become generally known to any
available for use by the public other than as a result of Executive's acts or
omissions to act.

        5. INVENTIONS AND PATENTS. Executive agrees that any inventions,
innovations or improvements in Employer's or its subsidiaries' method of
conducting their business (including new contributions, improvements, ideas and
discoveries, whether patentable or not) conceived or made by him during his
employment pursuant to this Agreement belong to Employer or its subsidiaries, as
the case may be. Executive shall perform any actions reasonably requested by the
Board of Directors of Employer to establish and confirm such ownership.
Executive shall not claim any right, title or interest of any kind with respect
to such inventions, innovations or improvements.


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        6. REMEDY FOR BREACH. In the event of a breach by Executive of any of
the provisions of Sections 2, 3, 4, or 5, Employer or its subsidiaries, as the
case may be, may, in addition to other rights and remedies existing in their
favor, apply to any court of competent jurisdiction for specific performance
and/or injunctive or other relief in order to enforce or prevent any violations
of the provisions thereof.

        7. TERMINATION.

           (A) TERMINATION FOR CAUSE. Employer may terminate the employment of
Executive for cause at any time prior to the expiration of the term of this
Agreement. For purposes of this Agreement, "cause" shall mean Executive's (1)
conviction of a felony, (2) willful misconduct or gross negligence in the
conduct of his duties hereunder that continues after written notice thereof to
Executive, or (3) willful act of fraud or theft. In the event of the termination
for cause under this Section 7(A), Executive shall be entitled to receive (X)
his base compensation provided for in Section 1(C) hereof through the date of
termination of his employment, and (Y) all other amounts due him hereunder to
the extent already earned and not theretofore paid (including any bonus payable
under Section 1(D) for any fiscal year previously ended to the extent not 
theretofore paid).

           (B) TERMINATION WITHOUT CAUSE. Employer may in its sole discretion,
terminate the employment of Executive for any reason upon written notice to
Executive, which termination shall become effective immediately upon delivery of
such notice. In the event of termination without cause under this Section 7(B),
Executive shall be entitled to continue to receive all compensation and benefits
described in Sections 1(C), 1(D) and 1(E) until the later of (1) the expiration
of the Initial Term or Renewal Term then in effect, or (2) the one year
anniversary of the delivery of notice of termination of employment under this
Section 7(B).

           (C) TERMINATION BY EXECUTIVE. Executive may, in his sole discretion,
terminate his employment for any reason upon six (6) months' prior written
notice to Employer, which termination shall become effective upon the earlier of
(1) the expiration of the six-month period following the delivery of such
notice, or (2) any earlier date designated by Employer in a written notice to
executive. In the event of termination by Executive under this Section 7(C),
Executive shall be entitled to (X) to receive his base


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compensation provided for in Section 1(C) through the effective date
of termination of his employment, (Y) to receive his base compensation provided
for in Section 1(C) for three (3) months following the effective date of
termination of his employment, and (Z) to receive all other amounts due him
hereunder to the extent already earned and not theretofore paid (including a
bonus payable under Section 1(D) for any fiscal year previously ended to the
extent not theretofore paid).

           (D) TERMINATION BY DEATH OR DISABILITY. In the event of Executive's
death or permanent disability while in the employ of Employer, which disability
in the opinion of a physician selected by Employer renders him incapable of
performing the services contemplated under this Agreement, in addition to other
provisions of this Agreement, the following provisions shall apply:

               (1) Employer shall pay to Executive or the estate of Executive
the base compensation which would otherwise be payable to the Executive
hereunder for a period of (1) year after such permanent disability or death
occurs.

               (2) An amount shall be determined equal to the incentive
compensation, if any, to which Executive would have been entitled if he had
lived or remained capable of performing the contemplated under this Agreement,
and a portion thereof based on the pro rata part of the year elapsed to the date
of his death or permanent disability shall be paid in a lump sum to Executive,
his estate or his personal representative, as the case may be.

               (3) Either of the benefits provided for in Section 7(D)(1) or
7(D)(2) may, at Executive's election, be paid to his designated beneficiary or
beneficiaries in lieu of his personal representative.

               (4) In addition to other benefits outlined herein, Executives
shall be entitled to all long-term disability pay and death benefit protection
provided through Employer and/or insurance programs in effect from time to time.

        8. RENEWAL. Unless either party gives written notice to the other patty
at least six (6) months prior to the expiration of the Initial Term or any
Renewal Term then in effect, this Agreement shall automatically be renewed for
successive one (1) year Renewal


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Terms upon the same terms and conditions as were in effect as of the
commencement date of such Renewal Term.

        9. NO SET-OFF. Neither Employer nor its subsidiaries shall have any
right of set-off counterclaim, in respect of any claim, debt or obligation,
against the payments or benefits to be made or provided to Executive under this
Agreement.

        10. NOTICES. All notices, requests, demands and other communications
which are required or may be given under this Agreement shall be in writing and
shall be deemed to have been duly given if delivered personally or mailed, first
class mail, postage prepaid, return receipt requested, or by any other express
delivery technique calling for receipted delivery, as follows:

        (a)     If to Executive:

                       Terry L. Guckes, Ph.D.
                       145 Grey Fox Run
                       Chagrin Falls, Ohio 44022
                       Telephone: (216) 247-1522

        (b)     If to Employer or its subsidiaries:

                       OM Group, Inc.
                       3800 Terminal Tower
                       Cleveland, Ohio 44113
                       Attn: M. J. Scott, Secretary
                       Telephone: (216) 781-0083
                       Facsimile: (216) 781-0902

                       With a copy to:

                       Squire, Sanders & Dempsey
                       4900 Society Center
                       127 Public Square
                       Cleveland, Ohio 44114
                       Attn: Paul B. Campbell, Esquire
                       Telephone: (216) 479-8666
                       Facsimile: (216) 479-8780

or such other address or to the attention of such other person as the recipient
shall have specified by prior written notice to the sending party. Any notice
under this Agreement will be deemed to have been given when so delivered or
mailed.


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        11. SEVERABILITY. Whenever possible, each provision of this Agreement
shall be interpreted in such manner as to be effective and valid under
applicable law, but 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
jurisdiction, such invalidity, illegality or unenforceability will not effect
any other provision or any other provision or any other jurisdiction as if such
invalid, illegal or unenforceable provision had never been contained herein.

        12. ENTIRE AGREEMENT. This Agreement, those documents expressly referred
to herein and other documents of even date herewith embody the complete
agreement and understanding among the parties and supersede and preempt any
prior understandings, agreements or representations by or among the parties,
written or oral, which may have related to the subject matter hereof in any way.

        13. COUNTERPARTS. This Agreement may be executed on separate
counterparts, each of which is deemed to be an original and all of which taken
together constitute one and the same agreement.

        14. SUCCESSORS AND ASSIGNS. This Agreement is intended to bind and inure
to the benefit of and be enforceable by Executive, Employer, and their
respective successors and assigns; provided that Executive may not assign his
rights or delegate his obligations hereunder without the prior written consent
of Employer. Neither Employer nor its subsidiaries may assign their respective
rights hereunder with respect to the employment of Executive to any person or
entity other than to any of controlled subsidiaries of the Employer.

        15. CHOICE OF LAW. All questions concerning the construction, validity
and interpretation of the employment provisions of this Agreement will be
governed by the internal law, and not the law of conflicts, of the State of
Delaware.

        16. AMENDMENTS AND WAIVERS. Any provision of this agreement may be
amended or waived only with the prior written consent of Executive and Employer.


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        17. ALTERNATIVE DISPUTE RESOLUTION. Any dispute arising out of this
Agreement (except a dispute relating to this Section 17 or Exhibit A attached
hereto) shall be submitted to the Alternative Dispute Resolution procedures
described in Exhibit A attached hereto.


        IN WITNESS WHEREOF, Employer has caused this Agreement to be executed by
its duly authorized officer and Executive has executed this Agreement as of the
date first above written.


                                  "EMPLOYER"

                                  OM GROUP, INC.



                                  By:  /s/ Eugene Bak

                                  Its: President and Chief Operating Officer



                                  "EXECUTIVE"


                                  /s/ Terry L. Guckes















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