This book constitutes the refereed proceedings of the 19th International Conference on Information Security, ISC 2016, held in Honolulu, HI, USA, in September 2016. The 19 revised full papers presented together with 7 short papers were carefully reviewed and selected from 76 submissions. The conference focuses on following subjects technical aspects of information security, cryptanalysis, cryptographic protocols, network and systems security and access control, privacy and watermarking, software security, encryption, signatures and fundamentals.