This book constitutes the refereed proceedings of the First International Conference on Rough Sets and Knowledge Technology, RSKT 2006, held in Chongqing, China in July 2006.

The 43 revised full papers and 58 revised short papers presented together with 15 commemorative and invited papers were carefully reviewed and selected from a total of 503 submissions. The papers are organized in topical sections on rough computing, evolutionary computing, fuzzy sets, granular computing, neural computing, machine learning and KDD, logics and reasoning, multiagent systems and Web intelligence, pattern recognition, system engineering and description, and real-life applications based on knowledge technology.