Abstract : The U.S. Army is increasingly staffed with knowledge workers-professionals who use information as their main input and whose major products are distillations of that information. The U.S. Army Construction Engineering Research Laboratories (USACERL) is developing a computer-based performance support environment intended to improve the productivity of Army knowledge workers. This product, the Knowledge Worker System (KWS), is designed to help work groups enhance their performance while documenting and distributing business process information. As part of this research, USACERL has identified the need to measure productivity among knowledge workers to recognize any gains that can be attributed to implementation of KWS. The objectives of this interim report are to compile from the literature the most promising approaches to measuring knowledge worker productivity, and to discuss which methodologies may work best in specific knowledge-work environments. Knowledge Worker System (KWS), Productivity, Performance.