This introductory book provides a sound foundation for operational security risk practitioners as well as others with an interest or responsibility for security in our rapidly changing and often unpredictable global environment. It is not intended as an alternative to specialised texts on security issues, but rather as a supplement to theoretical perspectives and practical guidelines including standards on the subject. As the nature and character of risk in the modern world continues to evolve and present new and unanticipated challenges, there is a need for innovative approaches to protective security which focus on the operational level where risks impact most upon people as well as the information systems, property and general business and community activities that define their everyday lives. This book makes an important contribution to this goal. Security-related risks are an unavoidable part of day-to-day life and need to be treated seriously by all organisations regardless of size or location. But as the late German sociologist Ulrich Beck observed in his seminal work on the contemporary nature of risk, World Risk Society, in the modern world risk and responsibility are intrinsically connected. Therefore, although risks can be categorised under any number of headings such as personnel, property, technological, legal, regulatory, financial and reputational, what is ultimately needed by those tasked with the responsibility of managing risk is a framework which acknowledges the fluidity of risk but which at the same time places human activity as the focal point of mitigation efforts. Dr Tony Zalewski's book makes an important contribution to this goal.