Drowning has three major causes: (1) inability to swim and/or lack of a personal flotation device; (2) hypothermia; and (3) abuse of alcohol or drugs. Defenses against drowning include: (1) proper use of personal flotation devices; (2) learning swimming and flotation techniques; (3) understanding reduction of heat loss in cold water; and (4) understanding the effects of alcohol on swimmers. (JN)