In the 1950s, researchers devised the best methods of ventilation. In the 1960s, a method of maintaining circulation and ventilation simultaneously was introduced. In the 1970s, refinements of the understanding of the mechanisms of blood flow during CPR were defined and were accompanied by an aggressive research effort to identify means to improve brain protection during and after cardiac arrest. It is hoped that the fruits of this work will lead to knowledge of better ways to effect resuscitation and will maximize the quality of life in survivors of cardiac arrest.