Exhibit 10.1

May 1, 2007

Dear Kathy:

As per our recent conversations, I write to memorialize our agreement with
respect to your termination from Millipore. Before I do that, however, I want to
thank you for the significant contributions you have made to the company over
the years and especially in the two and a half years we have worked together.

As to your termination:

 

  1. You will remain in your current position as Corporate Vice President and
Chief Financial Officer until August 15, 2007.

 

  2. After August 15, 2007 you will step down as CFO, but will remain a
Corporate Vice President reporting to me. In this capacity you will be available
to consult with your successor and me for the remainder of your employment and
will be expected to work part-time.

 

  3. Your employment will terminate on February 18, 2008. As this termination is
voluntary on your part, the Officer Severance Agreement entered into between you
and the company on November 18, 2003 will not apply to your termination.

 

  4. If you remain with Millipore as an employee on the terms described above
until February 18, 2008, you will receive a Millipore Incentive Plan payment for
2007 at 55% of your base pay times the corporate multiplier for 2007. You will
not receive an equity grant.

 

  5. Career counseling will be made available to you at a cost to the company
not to exceed $30,000.

 

  6. If you remain with Millipore as an employee on the terms described above
until February 18, 2008, you will be paid an additional $100,000 on or about
that time.

 

  7. Other than as described above, you will be treated the same as any other
employee whose employment has been voluntarily terminated.

If the above accurately describes our agreement, please sign, date and return
this letter.

Sincerely,

/s/ Martin Madaus

Martin Madaus, Ph.D.

Chairman, President and CEO

Agreed:

 

/s/ Kathleen B. Allen                                  
5/1/07                                          Kathleen B. Allen   Date: