Fast Software Encryption is now a 10-year-old workshop on symmetric crypt- raphy, including the design and cryptanalysis of block and stream ciphers, as well as hash functions. The ?rst FSE workshop was held in Cambridge in 1993, followed by Leuven in 1994, Cambridge in 1996, Haifa in 1997, Paris in 1998, Rome in 1999, New York in 2000, Yokohama in 2001, and Leuven in 2002. This Fast Software Encryption workshop, FSE 2003, was held February 24- 26,...