Jeff Cooper, president and founder of the American Pistol Institute, is probably the nation's foremost instructor on defensive weaponcraft. As such he teaches not only marksmanship, safety, and weapon mechanics, but also defensive mental conditioning. This booklet is a condensation of his current presentation on the theory individual, personal, defensive behavior. It is safe to say that a decisive majority of the victims of recent horrific murders, if they had read this short work and heeded what they read, would be alive today.