The purpose of the International Conference on Security and Cryptography (SECRYPT-2006) is to bring together researchers, mathematicians, engineers and practitioners interested on security aspects related to information and communication. Theoretical and practical advances in the fields of cryptography and coding are a key factor in the growth of data communications, data networks and distributed computing. In addition to the mathematical theory and practice of cryptography and coding, SECRYPT also focus on other aspects of information systems and network security, including applications in the scope of the knowledge society in general and information systems development in particular, especially in the context of e-business, internet and global enterprises.