For more information, contact:

Jim Donaldson Advanced Energy Industries, Inc. 970.407.6374

Marna Shillman Advanced Energy Industries, Inc. 970.407.6280 marna.shillman@aei.com

Milpitas, California (December 13, 2000)—Advanced Energy Industries, Inc. (Nasdaq: AEIS) has named Jim Guilmart Senior Vice President of Sales. Mr. Guilmart has responsibility for all of AE's strategic sales activities. In announcing the new appointment, AE President and COO Hollis Caswell said, "Jim has demonstrated a strong track record in critical sales positions. He brings the leadership and strategic skills AE needs to aggressively expand our market share, to integrate the product lines of the companies we've recently acquired, and to enhance and strengthen our end-user channels."

Mr. Guilmart has direct oversight of sales operations in North America, the Pacific Rim, Japan, and Europe, including OEM, end-user, and industrial sales. In addition to growing market share in AE's well-established markets, Mr. Guilmart will focus on sales to new markets outside AE's traditional semiconductor base.

Mr. Guilmart brings over 20 years of senior sales and marketing experience to his new position. He joined AE in September 1999 as Director of the Applied Materials Business Unit.

Advanced Energy is a global leader in the development, marketing, and support of integrated technology solutions that are central in the manufacture of semiconductors, data storage products, and flat panel displays as well as other mission-critical power applications. Original equipment manufacturers and end- users around the world depend on AE products when plasma-based technology plays a vital role in their manufacturing process. AE offers a comprehensive suite of key subsystems for vacuum process systems including power conversion and control solutions, process monitoring and machine control tools, ion-beam sources, dynamic temperature control and measurement products, and plasma abatement technologies. AE technology solutions are sold and supported globally by direct offices, representatives, and distributors. Founded in 1981, AE is a publicly held company traded on Nasdaq under the symbol AEIS.