Security Protocols ; 13th International Workshop, Cambridge, UK, April 20-22, 2005, Revised Selected Papers

Welcome to the Proceedings of the 13th International Security Protocols Wo- shop. As usual, our meeting in Cambridge was just the beginning. After that, position papers were revised (often more than once) and transcripts were c- culated, discussed, and edited several times: our intention was not to produce a sterile record of who said what, but to share some promising lines of enquiry into interesting problems. Now we bring these proceedings to a wider audience so that you can join in. Our theme this time was “The systemlikes youandwants to be yourfriend.” Security is usually seen as making systems more di?cult for humans to use.