MKS Instruments (MKSI) 8-K Departure of Directors or Principal Officers

Exhibit 99.1

Summary of 2008 Compensatory Arrangements with Executive Officers*

Executive Officer	Annual Salary
Leo Berlinghieri, Chief Executive Officer and President	$	530,000
Gerald G. Colella, Vice President, Chief Business Officer and Acting Group VP, PRG Products	$	365,000
John T.C. Lee, Group VP CIT and Ion Systems Products	$	275,000
Frank Schneider, Vice President & General Manager, Ion Systems	$	242,050
John A. Smith, Vice President and Chief Technology Officer	$	295,000
William D. Stewart, Vice President & General Manager, Vacuum Products Group	$	260,000
Ronald C. Weigner, Vice President and Chief Financial Officer	$	275,000

* Mr. Schneider was an executive officer of MKS Instruments, Inc. (the “Company”) during the year ended December 31, 2007 and constitutes a “named executive officer” under the rules of the Securities and Exchange Commission. Mr. Schneider is no longer an executive officer of the Company.