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                                                                   Exhibit 10.21

August 5, 1999

Mr. Kazuo Kimata
President and Chief Executive Officer
MECS CORPORATION
28 Jhonou, Kitaima
Bisai-shi, Aichi 494-8508
Japan

Re: Cooperation Agreement

Mr. Kimata:

By this letter we formalize our understandings with respect to the interim
cooperation contemplated by our Term Sheet dated August 5, 1999 and create the
framework for shared success.  Pending the conclusion of "Phase II" or any
earlier termination of our efforts to conclude de Definitive Agreements, the
parties acknowledge that it will be highly desirable to make joint efforts with
respect to specific opportunities in Japan.  For example,  both MECS and Asyst
have made or contemplate making proposals to Applied Materials Japan, Anelva,
Ulvac and Sony's Oem Metrology Group.  These prospective customers, in turn,
have expressed a desire to have us present our SMIF and robotics systems to them
in a more integrated manner.  If such a joint proposal were accepted, then
corresponding work would have to be done in a closely coordinated manner,
invoiced, warrantied and supported.  If our joint proposal is accepted by the
relevant customer, we agree to proceed on the basis of the terms set forth in
our joint proposal, notwithstanding the failure to conclude the Definitive
Agreements.

Until either of us elects to discontinue these efforts, we each agree to
negotiate in good faith the specific written terms of any joint proposal to the
previously identified prospective customers, and any other prospect subsequently
mutually agreed upon in writing, and thereafter to implement such proposal as
agreed in writing.  In some cases, Asyst will take the lead in developing an
opportunity, presenting the proposal and executing the agreed upon scope of
work.  In other cases, MECS will take the lead.  There will be numerous
variations of the foregoing.  In all cases, a party will defer to the other's
area of expertise.  Collection, payment, warranty and support terms between the
parties will be specifically negotiated in each instance.  Neither party can
bind the other to any terms with a third party without the prior express written
approval of the other.  No partnership is intended or created.  Each project
will therefore be a specific contractual arrangement, with one party acting as a
subcontractor to the other, as mutually agreed and tailored to specific
circumstances.  Customary terms will be relied upon whenever

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possible, including with respect to indemnification. Such cooperation does not
create a license to either party's intellectual property rights, unless
specifically agreed to in a written and detailed scope of work for a specific
project. Prior to embarking on the negotiation of any joint project, the parties
will enter a standard mutual confidentiality and nonuse agreement customized to
the specific project.

If the foregoing is acceptable, kindly sign and return a copy of this letter to
me as soon as possible.

Sincerely,



/s/ Mihir Parikh
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Mihir Parikh
Chairman and Chief Executive Officer


Agreed as of the date hereof.


/s/ Kazuo Kimata
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Kazuo Kimata
President and Chief Executive Officer

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