OverviewNations, organizations, and individuals face increasingly complex and sometimes worrying risks to their security from cyber-attacks, crime, terrorism, and other sources. In this environment, protective security has become an intrinsic feature of contemporary social life, as risks continually evolve, new types of threat emerge, and new ways of countering them are developed.In his essential new book, world-leading security expert Paul Martin sets out the ten most important guiding principles of protective security and resilience. Clearly expressed in the form of simple rules of thumb, they help to solve complicated problems for which there are no textbook solutions. The rules offer a powerful toolkit, designed to work in many different situations, including the cyber domain. When we are faced with novel problems requiring complex decisions, it is easy to focus on the wrong things. These rules remind us what really matters. If you read only one book about security, it should be this one.