Today's society can no longer function without information technology. Essential infrastructure including the transportation system, banking, the entertainment industry, the health care system, government, the military and the education system can no longer survive without modern technology. This increasing dependence on information technology creates new opportunities for the benefit of society. However, it also opens an avenue that can be exploited for illicit purposes. The stakes are high and many attacks go undetected or unreported. In addition to losses such as data or other forms of intellectual property, financial theft or the shut down of infrastructure, computer security attacks that target critical infrastructure such as nuclear power plants has the potential to cause human casualties on a massive and unprecedented scale. This book provides a discussion on a wide variety of viewpoints on some of the main challenges facing secure systems. This book will therefore be of major interest to all researchers in academia or industry with an interest in computer security. It is also relevant to graduate and advanced level undergraduate students who may want to explore the latest developments in the area of computer and information security.