Despite the 8,000 drownings that occur annually in the United States, procedures for aquatic first aid are currently limited to mouth-to-mouth resuscitation, while cardiopulmonary resuscitation (CPR) must be delayed until the victim is transported to a solid surface for conventional closed-chest cardiac compressions. We discuss techniques of positioning a victim on the rescuer's chest and initiating CPR, on site. Respiratory support was provided with a slightly modified scuba regulator, and procedures were tested on an instrumented aquatic CPR mannequin in the water and anesthetized dogs on land. Most results were within specified criteria for successful CPR.