This book constitutes the refereed proceedings of the 8th European Symposium on Research in Computer Security, ESORICS 2003, held in Gjovik, Norway in October 2003. The 19 revised full papers presented were carefully reviewed and selected from 114 submissions. Among the topics addressed are signature control, access control, key exchange, broadcast protocols, privacy preserving technologies, attack analysis, electronic voting, identity control, authentication, security services, smart card security, formal security protocols analysis, and intrusion detection.