This volume coherently present 24 thoroughly revised full papers accepted for the ECAI-94 Workshop on Agent Theories, Architectures, and Languages. There is currently considerable interest, from both the AI and the mainstream CS communities, in conceptualizing and building complex computer systems as collections of intelligent agents. This book is devoted to theoretical and practical aspects of architectural and language-related design and implementation issues of software agents. Particularly interesting is the comprehensive survey by the volume editors, which outlines the key issues and indicates, via a comprehensive bibliography, topics for further reading. In addition, a glossary of key terms in this emerging field and a comprehensive subject index is included.