For more information, contact:

Mike El-Hillow Advanced Energy Industries, Inc. 970.407.6570

Cathy Kawakami Advanced Energy Industries, Inc. 970.407.6732 cathy.kawakami@aei.com

FORT COLLINS, Colo., September 19, 2002—Advanced Energy Industries, Inc., (Nasdaq: AEIS) today announced that Douglas S. Schatz, chairman, president and chief executive officer will assume the position of chief operating officer on an interim basis, replacing James F. Gentilcore who has left the Company. The Company has initiated a search for a new COO.

Commenting on the change, Mr. Schatz said, “Our recent acquisitions of Aera Japan Ltd., and Dressler HF Technik GmbH have significantly expanded our product offerings and market opportunities internationally and are important ingredients to our strategy of providing more comprehensive solution sets to our customers. We are extremely well-positioned to take advantage of the industry’s movement to closer partnerships throughout the entire supply chain, and it is important for me to be more directly involved in our day-to-day operations as we take our company to the next level.

“I want to thank Jim for his many contributions to AE over the last six years. Jim applied his many years of semiconductor industry experience to his various roles at AE, specifically as president of the EMCO and Voorhees divisions where he demonstrated his operations and leadership capabilities. As COO, he has been instrumental in the transition to and the success of our product division structure, which has created operational efficiencies. We wish him well in his future career endeavors.”

About Advanced Energy
Advanced Energy is a global leader in the development, marketing and support of components and sub-systems critical to plasma-based manufacturing processes used in the production of semiconductors, flat panel displays, data storage products, compact discs, digital video discs, architectural glass, and other applications that require precise thin-film processes. AE offers a comprehensive line of technology solutions in power, flow and thermal management, plasma and ion beam sources, and integrated process monitoring and control to original equipment manufacturers (OEMs) and end-users around the world. AE operates in regional centers in North America, Asia and Europe, and offers global sales and support through direct offices, representatives and distributors. Founded in 1981, AE is a publicly-held company traded on Nasdaq National Market under the symbol AEIS. For more information, please visit our corporate website: www.advanced-energy.com.

Safe Harbor Statement
This press release contains certain forward-looking statements subject to known and unknown risks and uncertainties that could cause actual results to differ materially from those expressed or implied by such statements. Such risks and uncertainties include, but are not limited to: the volatility and cyclicality of the semiconductor and semiconductor capital equipment industries, fluctuations in quarterly and annual revenues and operating results, Advanced Energy’s ongoing ability to develop new products in a highly competitive industry characterized by increasingly rapid technological changes, our ability to successfully integrate acquired companies’ operations, and other risks described in Advanced Energy’s Form 10-K, Forms 10-Q and other reports and statements, as filed with the Securities and Exchange Commission. These reports and statements are available on the SEC’s website at www.sec.gov. Copies may also be obtained by contacting Advanced Energy’s investor relations at 970-407-6732. The company assumes no obligation to update the information in this press release.