The 5th International Conference on Information Security Practice and Expe- ence (ISPEC 2009) was held in Xi’an, China, April 13–15, 2009. The ISPEC conference series is an established forum that brings together - searchers and practitioners to provide a con?uence of new information security technologies, including their applications and their integration with IT systems in various vertical sectors. In previous years, ISPEC has taken place in Sin- pore (2005), Hangzhou, China (2006), Hong Kong, China (2007), and Sydney, Australia (2008). For all sessions, as this one, the conference proceedings were published by Springer in the Lecture Notes in Computer Science series. In total, 147 papers from 26 countries were submitted to ISPEC 2009, and 34 were ?nally selected for inclusion in the proceedings (acceptance rate 23%). The accepted papers cover multiple topics of information security and applied cryptography. Each submission was anonymously reviewed by at least three - viewers. We are grateful to the Program Committee, which was composed of more than 40 well-known security experts from 15 countries; we heartily thank them as well as all external reviewers for their time and valued contributions to the tough and time-consuming reviewing process. Inadditiontothe regularpaperpresentations,the programalsofeaturedfour invited talks by Yupu Hu, from Xidian University, China; Youki Kadobayashi, from Nara Institute of Science and Technology, Japan; Mark Ryan, from the University of Birmingham, UK; and Gene Tsudik, from the University of C- ifornia at Irvine, USA. We are grateful to them for accepting our invitation to speak at the conference.weiterlesen