This book constitutes the refereed proceedings of the Third International Conference on Information Systems Security, ICISS 2007, held in Delhi, India, in December 2007.

The 18 revised full papers and 5 short papers presented together with 4 keynote papers were carefully reviewed and selected from 78 submissions. The submitted topics in cryptography, intrusion detection, network security, information flow systems, Web security, and many others offer a detailed view of the state of the art in information security. The papers are organized in topical sections on network security, cryptography, architectures and systems, cryptanalysis, protocols, detection and recognition, as well as short papers.