SANTA CLARA, Calif. - April 5, 2005 - SigmaQuest™ Inc., the enterprise software company whose solutions provide unprecedented insight and actionable information to ensure product and process integrity, by collecting, aggregating and analyzing test and quality data, today announced that Plantronics, Inc. (NYSE:PLT), the world leader in communications headsets, has chosen the SigmaQuest SigmaSure Enterprise Edition to drive higher product yields and to provide real-time visibility into its globally-distributed design and manufacturing centers, and suppliers throughout the entire product lifecycle.

"Plantronics, a leader in voice communications for more than 40 years, is a welcome addition to the growing number of world class design and manufacturing organizations that use SigmaQuest solutions to gain improvements in yield and quality," said Nader Fathi, CEO of SigmaQuest.   "We are enthusiastic about having Plantronics use our newest product release, the SigmaSure Enterprise Edition, which is designed to provide globally distributed product and manufacturing organizations with the means to eliminate organization inefficiencies, reduce manufacturing-transformation costs and improve product quality and reliability.   This offering also provides customers with a single cohesive view of distributed test and manufacturing sites to improve overall product performance throughout the lifecycle while reducing costs and risks for high-volume and mission-critical products."

"After extensive research and evaluation, we selected the SigmaQuest solution as the best-of-class product performance intelligence system for our global operations," said Rick Frier, senior manager Global Test Engineering, Plantronics. "At Plantronics, we are committed to providing the highest level of product quality and SigmaSure Enterprise Edition will enhance our test and manufacturing processes."

About SigmaSure Enterprise Edition                                                                                                               

SigmaSure Enterprise is a suite of software that performs real-time capture and analysis of test and process data over the Web, letting engineers remotely manage test stations and control tester software across all manufacturing/production sites from their desktops to eliminate organization inefficiencies, reduce manufacturing-transformation costs and improve product quality and reliability. The Personalized Dashboard customizes analyses, reports, and alarms with information about the product, factory, and operator. Discovery Wizards detect which test stations, fixtures, and measurements are failing most often, and also provide insights into resolution and prevention.   SigmaTrace provides a complete genealogy record for each unit that is manufactured and shipped.   SigmaSure Enterprise Edition is available on all Linux, Windows, Unix and Mac platforms.

About Plantronics 

Plantronics introduced the first lightweight headset in 1962 and is recognized as the world leader in communications headsets. Plantronics headsets have been featured in numerous motion pictures and high-profile events, including Neil Armstrong's historic "One small step for man, one giant leap for mankind" transmission from the moon in 1969. A publicly held company headquartered in Santa Cruz, California, with approximately 3,900 employees, Plantronics maintains offices in 20 countries. For more information, go to www.plantronics.com or call (800) 544-4660.

About SigmaQuest 

SigmaQuest Inc. is an enterprise software company whose solutions provide unprecedented insight and actionable information to ensure product and process integrity, by collecting, aggregating and analyzing test and quality data. Its solutions enable global enterprises and their partners to optimize product time-to-market, cost and quality.   This is accomplished through personalized views of product quality information, pro-active alerts and comprehensive traceability - all in real time. The company is headquartered at 2901 Tasman Drive, Suite 109, Santa Clara, CA 95054.  It can also be reached at (408) 654-9401 or online at www.sigmaquest.com .

SigmaQuest is trademark of SigmaQuest, Inc.   All other trademarks and registered trademarks are the property of their respective owners.