This book constitutes the refereed proceedings of the 10th European Symposium on Research in Computer Security, ESORICS 2005, held in Milan, Italy in September 2005. The 27 revised full papers presented were carefully reviewed and selected from 159 submissions. Among the topics addressed are access control, security protocols, digital signature schemes, intrusion detection, voting systems, electronic voting, authorization, language-based security, network security, denial-of-service attacks, anonymous communications, and security analysis.