Drowning is death as caused by suffocation when a liquid causes interruption of the body's absorption of oxygen from the air leading to asphyxia. The primary cause of death is hypoxia and acidosis leading to cardiac arrest.

Near drowning is the survival of a drowning event involving unconsciousness or water inhalation and can lead to serious secondary complications, including death, after the event. Cases of near drowning are often given attention by medical professionals. Secondary drowning is death due to chemical or biological changes in the lungs after a near drowning incident.

In many countries, drowning is one of the leading causes of death for children under 14 years old. Children have drowned in wading pools and even bath tubs. The rate of drowning in populations around the world varies widely according to their access to water, the climate and the national swimming culture. For example, typically the United Kingdom suffers 450 drownings per annum or 1 per 150,000 of population whereas the United States suffers 6,500 drownings or around 1 per 50,000 of population. Drowning related injuries are the fifth most likely cause of accidental death in the US. In some regions, drowning is the second most likely cause of injury and death for children after car accidents. The rate of near drowning incidents is unknown.

Victims are more likely to be male, young or adolescent. Surveys indicate that 10% of children under 5 have experienced a situation with a high risk of drowning. The causes of drowning cases in the US are as follows:

• 44% are related to swimming
• 17% are related to boating
• 14% are unattributed
• 10% related to scuba diving
• 7% related to car accidents