Since the September 11thattacks, the scientific and engineering communities have been called upon to help the world respond to security challenges. This volume focuses on challenges involving multidisciplinary problem analysis and systems engineering approaches to security. It presents a comprehensive survey of state-of-the-art methods for the surveillance and protection of citizens and critical infrastructure against both natural and deliberate threats. The first section analyzes technical issues related to surveillance. Next, the book examines legislative, organization, and management issues with a specific emphasis on privacy concerns. Finally, the contributors discuss innovative solutions and new research topics garnering heightened attention.