Massive community efforts are devoted to delivering cardiopulmonary resuscitation (CPR) training to health professionals and lay people. However, although most people can successfully learn to perform CPR, skills retention is universally poor. Beginning as early as 2 weeks after initial training, CPR skills begin to deteriorate in a wide variety of subjects including nurses, physicians, emergency medical technicians, family members of patients with cardiac disease, and other lay people. Methods tested to improve retention are reviewed, and the role of practice and review is examined. The failure of many factors to improve retention of CPR skills is discussed. Finally, suggestions for improvement in retention of CPR skills based on a review of the literature and pertinent theory are offered.