SAC'99 was the sixth in a series of annual workshops on Selected Areas in Cryptography. Previous workshops were held at Carleton University in Ottawa (1995 and 1997) and at Queen's University in Kingston (1994, 1996, and 1998). The intent of the annual workshop is to provide a relaxed atmosphere in which researchers in cryptography can present and discuss new work on selected areas of current interest. The themes for the SAC'99 workshop were: { Design and Analysis of Symmetric Key Cryptosystems { E cient Implementations of Cryptographic Systems { Cryptographic Solutions for Web/Internet...