This book constitutes the refereed proceedings of the 15th conference of the Canadian Society for Computational Studies of Intelligence, AI 2002, held in Calgary, Canada, in May 2002. The 24 revised full papers presented together with eight posters and ten abstracts of the graduate student symposium were carefully reviewed and selected from 52 full-length paper submissions. The book offers topical sections on agents, searching, neural nets, learning, probability, and natural language.