This book constitutes the refereed proceedings of the 6th Australasian Conference on Information Security and Privacy, ACISP 2001, held in Sydney, Australia, in July 2001. The 38 revised full papers presented together with three invited contributions were carefully reviewed and selected from a total of 91 submissions. Among the topics addressed are systems security, network security, trust and access cotrol, authentication, cryptography, cryptanalysis, digital signatures, elliptic curve cryptology, and secret sharing and threshold schemes.