Water is essential for life. Thirst is a pressing need which always has to be satisfied. Infants need 3 times more water than adults if the requirements is calculated according to body weight. A correct balance in the sensory, physical, chemical and bacteriological qualities of water make it drinkable. Two laws have been passed recently concerning drinking water in France: one deals with water for human consumption (January 3 1989 decree), and the other deals with drinkable bottled mineral water (June 3 1989 decree). Tap water and bottled water are under strict vigilance. For babies under 4 months of age, it is better to use bottled water with a low mineral content (nitrates less than 15 mg/l). Hard water is safe; water softeners are useful only for hot water. Fluorination supplies of water is good for dental health at a concentration of 1 mg/l. Plastic bottles are as safe as glass ones.