Book excerpt: Annotation This book constitutes the refereed proceedings of the 26th Annual International Conference on the Theory and Applications of Cryptographic Techniques, EUROCRYPT 2007, held in Barcelona, Spain in May 2007. The 33 revised full papers presented were carefully reviewed and selected from 173 submissions. The papers address all current foundational, theoretical and research aspects of cryptology, cryptography, and cryptanalysis as well as advanced applications.