Contact: Keithley Instruments, Inc.
28775 Aurora Road
Cleveland, Ohio 44139

Keithley Named to List of 50 Leading Electronics Companies

Cleveland, OH - January 26, 2005 - Keithley Instruments, Inc. (NYSE: KEI), a leader in solutions for emerging measurement needs, has been named in the electronics industry's annual Movers & Shakers issue as #4 on its list of Top 50 Companies to Watch in 2005. The issue is published by Reed Electronics Group, publishers of Electronic Business, Electronic News, Test & Measurement World, and Semiconductor International magazines. The list recognizes companies in the electronics industry based on innovation and product development.

"While we're very excited about the growth prospects for many of our product lines and market segments during the coming years, it is gratifying to see others outside our company share in our enthusiasm for the business," says company Chairman, President and CEO Joseph P. Keithley.

About Keithley Instruments. With more than 50 years of measurement expertise, Keithley Instruments ( has become a world leader in advanced electrical test instruments and systems from DC to RF (radio frequency) geared to the specialized needs of electronics manufacturers for high performance production testing, process monitoring, product development, and research. By building upon our strength in electrical measurement solutions for research, Keithley has become a production test technology leader for the semiconductor, wireless, optoelectronics, and other precision electronics segments of the worldwide electronics industry. The value we provide to our customers is a combination of precision measurement technology and a rich understanding of their applications to improve the quality, throughput, and yield of their products.

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