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August 4, 1994


Ed Norton
355 Edgehill Way
San Francisco, CA 94127

Facsimile Delivery:  759-1435

Dear Ed:

We are pleased to offer you a position as Vice President of Services.  This
position reports directly to Tom Tomasetti, President and Chief Executive
Officer, effective September 12, 1994.

The compensation and benefits you will receive upon employment include:

 .    $135,000 base salary per year

 .    Eligible for $20,000 Corporate Bonus (on an annual fiscal year basis):

     - $10,000 if the company meets certain financial goals.  The goals will
     include both revenue and profits and are the same goals that all members of
     the executive team will be measured against.  These goals must be approved
     by the Board of Directors.

     - $10,000 if executive meets specific MBO goals.  The customized objectives
     will be determined by Tom Tomasetti.

 .    Eligible for additional $30,000 annual bonus based on revenue and profit of
     the Consilium Service Department.  After joining Consilium, executive and
     Tom Tomasetti will mutually establish a revenue and profitability target
     for 1995 against which executive's bonus will be measured.  The bonus plan
     will pay $30,000 at target and be structured in a way such that significant
     over-achievement may result in additional payments of up to 100% of the on-
     target amount.  Bonuses under this plan can be structured to be paid out
     quarterly.  This program may not be fully outlined by the beginning of Q1
     1995, however, any earned bonus will be retroactive to Q1 1995. (November
     1, 1994)

 .    Management will recommend that the Board of Directors grant you an option
     pursuant to the Company's Stock Option Plan to purchase 50,000 shares of
     the Company's common stock at the purchase price equal to the fair market
     value of the stock on the date of the grant.  The option will be subject to
     the Company's standard option agreements and plan, including vesting over a
     four year term.
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 .    In the event that the Company terminates your employment with Consilium for
     reasons other than gross misconduct as described in the Employee handbook,
     you shall receive a severance package consisting of three month's salary
     paid semi-monthly and health benefits.  Except as expressly described in
     this paragraph, you shall not be entitled to receive any other benefits
     from Consilium.

 .    Medical, dental, vision, life and disability insurance as described in
     Benefits Summary.

 .    Ability to participate in Consilium's Employee Stock Purchase Plan (ESPP)

 .    Ability to establish and contribute to your own savings and retirement
     (401K) account

Consilium is dedicated to:

 .    Providing high quality, leading-edge computer integrated manufacturing
     solutions that enable our customers to achieve their manufacturing
     objectives
 .    Ensuring a positive, growth oriented team environment for our employees
 .    Providing an excellent return to our shareholders.

We are confident that you will use your skills at Consilium to help us continue
this mission.

Your employment with Consilium is voluntarily entered into and is for no
specified period of time.  As a result, you are free to resign at any time, for
any reason or for no reason.  Similarly, Consilium is free to conclude its at-
will employment relationship with you at any time, with or without cause.

In the event of any dispute or claim relating to or arising out of our
employment relationship or this agreement including but not limited to any
claims of wrongful termination or age or other discrimination, you and Consilium
agree that all such disputes shall be fully and finally resolved by binding
arbitration conducted by the American Arbitration Association in San Jose,
California.  However, we agree that this arbitration provision shall not apply
to any dispute or claims relating to or arising out of the misuse or
misappropriation of Consilium's trade secrets or proprietary or confidential
information.

To satisfy Federal Immigration Laws, you must provide proof that you are a
United States citizen or are eligible for legal employment in the United States.
Documents which are acceptable for this purpose include:

 .    Driver's License and Birth Certificate/Social Security Card, or
     Passport, or Alien Registration card with photograph.

You must provide Consilium with a copy of the requested document(s) within three
business days from your date of hire.

This letter, and any additional written proprietary rights agreement between
Consilium and you, define the terms of your employment and supersedes all prior
agreements, both written and verbal.  This letter can not be modified or amended
unless done so in writing and signed by an authorized Consilium representative
and yourself.
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We are very happy to confirm your employment offer with this letter and we look
forward to you joining the Consilium staff.  Please indicate your acceptance of
this offer by signing one copy of this letter and returning it to the Human
Resources Department.  If you have any questions about the offer, please feel
free to contact me directly.

Sincerely,

/s/ Linda Kata Ujihara

Linda Kato Ujihara
Director, Human Resources

cc:  T. Tomasetti

I agree to and accept employment with Consilium on the terms set out above, and
I certify that I have responded fully and accurately to all inquiries made of me
by Consilium during the pre-employment process with regard to employment history
and salary, education and criminal or civil lawsuits.

/s/ Edward Norton, August 5, 1994
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Signature & Date