May 18, 1999

Mr. Gregory S. Baletsa
c/o GSI Lumonics Inc.
39 Manning Road
Billerica, MA, 01821, U.S.A.

Dear Greg:

We refer you to the letter agreement dated April 21, 1999, sent to you by GSI
Lumonics and accepted by you, which sets out certain severance and termination
benefits which you will be entitled to in certain circumstances (the "Original
Agreement").  This letter (the "Amending Agreement") is intended to amend that
Original Agreement as follows:

1.   The term "Company" as defined in the Original Agreement shall include any
     corporation that is a direct or indirect subsidiary of GSI Lumonics Inc.

2.   Notwithstanding anything to the contrary contained in the Original
     Agreement, in the event that you voluntarily terminate your employment with
     the Company at any time on or before September 22, 1999, you shall be
     entitled to receive from the Company an amount equal to your Total
     Compensation multiplied by a factor of 12. Such amount shall be payable as
     follows:

     (a)  50% 30 days after the Date of Termination;

     (b)  the balance in equal consecutive monthly payments which shall be paid
          on the first day of each month without interest commencing on the 1st
          day of the month following the Date of Termination;

Any term used herein shall have the meaning ascribed to such term in the
Original Agreement.

Please signify your acceptance of the amendments set out herein by signing and
returning to the Company the enclosed copy of this letter.

Sincerely yours,
GSI LUMONICS INC.


Per:    "Michael W. Lupiano"
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Agreed to this 1st day of June , 1999.

/s/ "Greg S. Baletsa"
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Signature

Greg S. Baletsa
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