Exhibit 99.1

 GSI GROUP ANNOUNCES CEO'S INTENT TO RETIRE AND APPOINTMENT OF EXECUTIVE SEARCH
                                      FIRM

     BILLERICA, Mass., Nov. 18 /PRNewswire-FirstCall/ -- GSI Group Inc.,
(Nasdaq: GSIG) announced the appointment of the executive search firm G. A.
Partners to assist the Board of Directors in identifying a successor to Charles
Winston, Chief Executive Officer, who will retire in 2006. The Board of
Directors, after evaluating a number of executive search firms, selected Paul
Gomory, principal of G.A. Partners, to lead the search process, based on his
experience and excellent track record.

     "Identifying Charles' successor is the most important priority for the
Board in the coming months. A Search Committee of three Board members has been
actively working on this, and is committed to devote whatever time and resources
are required to find and select the best candidate for this position", said
Richard Black, Chairman of the Board.

     Mr. Black continued, "Charles will remain as CEO until his successor is
appointed. And in an effort to accomplish a smooth and orderly transition,
Charles has also agreed to serve as a consultant and advisor to the Company and
the new CEO through 2008. In Charles' 18 years as CEO, a very long tenure nearly
unmatched in the world of high tech, Charles' contributions to the growth and
development of GSI have been immeasurable. We know that the bar has been set
very high and we have our work cut out for us to find a qualified successor."

     GSI Group Inc. supplies precision motion control products, lasers and
laser-based advanced manufacturing systems to the global medical, semiconductor,
electronics, aerospace and industrial markets. The Company's web site address is
http://www.gsig.com.

     Safe Harbor

     Certain statements in this news release may constitute forward-looking
statements within the meaning of the United States Private Securities Litigation
Reform Act of 1995, Section 27A of the United States Securities Act of 1933 and
Section 21E of the United States Securities Exchange Act of 1934. These
forward-looking statements may relate to anticipated financial performance,
management's plans and objectives for future operations, business prospects,
outcome of regulatory proceedings, market conditions, tax issues and other
matters. All statements contained in this news release that do not relate to
matters of historical fact should be considered forward-looking statements, and
are generally identified by words such as "anticipate," "believe," "estimate,"
"expect," "intend," "plan," "objective" and other similar expressions. Readers
should not place undue reliance on the forward- looking statements contained in
this news release. Such statements are based on management's beliefs and
assumptions and on information currently available to management and are subject
to risks, uncertainties and changes in condition, significance, value and
effect. Other risks include the fact that the Company's sales have been and are
expected to continue to be dependent upon customer capital equipment
expenditures, which are, in turn, affected by business cycles in the markets
served by those customers. Other factors include volatility in the semiconductor
industry, the risk of order delays and cancellations, the risk of delays by
customers in introducing their new products and market acceptance of products
incorporating subsystems supplied by the Company, similar risks to the Company
of delays in its new products, our ability to continue to reduce costs and
capital expenditures, our ability to focus R&D investment and integrate
acquisitions and other risks detailed in reports and documents filed by the
Company with the United States Securities and Exchange Commission and with
securities regulatory authorities in Canada. Such risks, uncertainties and
changes in condition, significance, value and effect, many of which are beyond
the Company's control, could cause the Company's actual results and other future
events to differ materially from those anticipated. The Company does not,
however, assume any obligation to update these forward-looking statements to
reflect actual results, changes in assumptions or changes in other factors
affecting such forward-looking statements.

     GSI-G

     Raymond Ruddy, Investor Relations of GSI Group, +1-978-439-5511 ext. 6170.

SOURCE  GSI Group Inc.
     -0-                             11/18/2005
     /CONTACT:  Raymond Ruddy, Investor Relations of GSI Group,
+1-978-439-5511 ext. 6170 /
     /First Call Analyst: /
     /FCMN Contact: /
     /Company News On-Call:  http://www.prnewswire.com/comp/107189.html/
     /Website:  http://www.gsig.com /
     (GSIG)