comprehensively surveys and explains the highly technical area of high security locks in a way that is accessible to a wide audience. Well over 100 different locks are presented, organized into 6 basic types. Each chapter introduces the necessary concepts in a historical perspective and further categorizes the locks. This is followed by detailed 'how it works' descriptions with many pictures, diagrams and references. The descriptions are based on actual dissections of the real locks.The scope is limited to key operated mechanical locks, thus keyless combination locks and digital locks are not covered. The book does not deal with routine locksmithing topics such as installation and servicing of locks. The sensitive area of picking and bypassing of locks is dealt with only at a high level without giving detailed information that would be unacceptable in the wrong hands.