This document provides information and instructions on performing basic life support (BLS) including cardiopulmonary resuscitation (CPR). It discusses recognizing when CPR is needed, proper techniques for chest compressions and rescue breathing in adults and infants, treating choking in conscious and unconscious victims, complications that can arise from CPR, and precautions to take when using manikins for practice. The goal of CPR is to provide oxygen to the brain until more advanced medical help arrives to revive heart and lung function. Immediate initiation of CPR and the use of an automated external defibrillator are critical for survival of cardiac arrest victims.