Police officers are the protective barrier standing between the public on one side and lawlessness on the other - the so-called "thin blue line." A high-stress job, officers face daily interactions in stressful situations where the element of risk is always lurking. An officer's main duty is to maintain law and order within a community, which means they are regularly face to face with citizens and out patrolling the streets. This book looks at the duties of police officers in crime prevention, the apprehension of offenders, and emergency situations.