As you read this, somewhere in California one law enforcement agency is providing mutual aid to another. Mutual aid is an everyday occurrence in a state as large and diverse as California. This is the continuation of the decades-long process of “neighbor helping neighbor.” The law enforcement mutual aid system is an ongoing cooperative effort among law enforcement agencies to ensure an effective and organized response to a wide range of emergencies. There is a misconception that mutual aid is something used only during a riot or disaster. The mutual aid system has been used successfully for many other situations, including large criminal investigations, deployment of special teams such as Special Weapons and Tactics Teams, Bomb Squads, etc.