Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

As part of its effort to reduce costs during the current slowdown in the semiconductor manufacturing industry, MKS Instruments, Inc. (the "Company") has reduced the salaries of its executive officers and non-employee directors. The reductions were approved effective as of August 25, 2008. Beginning on such date, the salary of the President of the Company was decreased by 10%, and the salary of the other executive officers was decreased by 5%. In addition, cash compensation of the Chairman of the Board of Directors of the Company was decreased by 10% and the cash compensation of all other non-employee directors of the Company was decreased by 5%.

Reduced compensation amounts are as set forth in the exhibits attached to this Report. Such reductions shall remain in place until otherwise determined by the Board of Directors or Compensation Committee, as appropriate.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

99.1 Salaries of Executive Officers, effective August 25, 2008

99.2 Cash Compensation of Non-Employee Directors, effective as of August 25, 2008

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