Drowning is a major global public health problem. Effective prevention of drowning requires programmes and policies that address known risk factors throughout the world. Surveillance, however, has been hampered by the lack of a uniform and internationally accepted definition that permits all relevant cases to be counted. To develop a new definition, an international consensus procedure was conducted. Experts in clinical medicine, injury epidemiology, prevention and rescue from all over the world participated in a series of "electronic" discussions and face-to-face workshops. The suitability of previous definitions and the major requirements of a new definition were intensely debated. The consensus was that the new definition should include both cases of fatal and nonfatal drowning. After considerable dialogue and debate, the following definition was adopted: "Drowning is the process of experiencing respiratory impairment from submersion/immersion in liquid." Drowning outcomes should be classified as: death, morbidity, and no morbidity. There was also consensus that the terms wet, dry, active, passive, silent, and secondary drowning should no longer be used. Thus a simple, comprehensive, and internationally accepted definition of drowning has been developed. Its use should support future activities in drowning surveillance worldwide, and lead to more reliable and comprehensive epidemiological information on this global, and frequently preventable, public health problem.