For more information, contact:

Richard Beck Advanced Energy Industries, Inc. 970.407.6204 dick.beck@aei.com

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

FORT COLLINS, Colo., August 15, 2001-Advanced Energy Industries, Inc. (Nasdaq: AEIS) today provided updated guidance to the third quarter outlook. Advanced Energy is an industry-leading provider of critical technology solutions for the manufacture of semiconductors, data storage products, and flat panel displays.

“We continue to experience order pushouts and cancellations that have forced the re-evaluation of our third quarter forecast,” said Doug Schatz, chairman and chief executive officer. “Our previous forecast was based on the best information available at the time, however we no longer believe our expectation of achieving revenue in the $43 million to $46 million range is realistic in this environment. Given the continued volatility and unpredictability of order patterns to date, we are modeling third quarter revenues in the $35 million to $39 million range. While we continue to gain market share, the share gains do not offset the pushouts and cancellations we are experiencing.”

“The timing of order re-acceleration is uncertain. Advanced Energy continues to make inroads into new product programs with its customers, and we believe our commitment to continued technology innovation well-positions the company for higher growth rates than the industry as we come out of the downturn,” continued Mr. Schatz.

Advanced Energy will report third quarter results on October 11.

Conference Call
Management will host a conference call today, August 15, 2001 at 5:00 pm Eastern time to discuss this press release. You may access this conference call by dialing 877-282-1086. International callers may dial 703-871-3017. For a replay of this teleconference, please call 703-925-2533, passcode 5470178. The replay will be available through Wednesday, August 22, 2001. There will also be a webcast available at www.advanced-energy.com.

About Advanced Energy
Advanced Energy is a global leader in the development, marketing, and support of technology solutions that are central in the manufacture of semiconductors, data storage products, and flat panel displays. Original equipment manufacturers (OEMs) 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 products for vacuum process systems, including power management, temperature sensing, dynamic temperature control, gas delivery management, process monitoring and machine control tools, ion-beam sources, 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 the Nasdaq National Market under the symbol AEIS. AE’s URL is 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, 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.