Within the last five to ten years, IT has entered all important areas in society. Today, enterprises and civilizations, as well as the survival of individuals as social and biological beings, depend strongly on well functioning, safe and secure IT. Unfortunately, focus on IT security has been fractionalized, detailed and often linked to non-business applications. Therefore, business, trade and industry have not been able to use existing IT security methodology and products. However, practices and insights are changing; without adequate and useful IT security functionality the IT society may only be a mirage. Among the leading issues discussed in this book are: IT security in retrospective - worthwhile inheritance for the future; exising IT security tools and methodology for modern IT environments including case studies; harmonization, standards, laws, regulation and ethics in IT security environments, and current and future prospects in technology, infrastructures, techniques and methodologies. This book contains the proceedings of the 13th International Conference on Information Security (SEC'97) sponsored by the International Federation for Information Processing (IFIP), and held in May 1997, Copenhagen, Denmark.