The Cambridge International Workshop on Security Protocols has now run for eight years. Each year we set a theme, focusing upon a speci?c aspect of security protocols, and invite position papers. Anybody is welcome to send us a position paper (yes, you are invited) and we don t insist they relate to the current theme in an obvious way. In our experience, the emergence of the theme as a unifying threadtakesplaceduringthediscussionsattheworkshopitself.Theonlyground rule is that position papers should formulate an approach to some unresolved issues, rather than being a description of a ?nished...