Fluoridation reaches everyone in a community, a feature which is both its greatest strength and greatest problem in terms of social policy. The first community water fluoridation scheme began in Grand Rapids, USA in 1945.It was Dean's work that led to the adoption of 10mg/l as the fluoride concentration in drinking water which represented the best trade off between substantial caries reduction and an acceptable level of the mildest forms of dental fluorosis. Fluoridation has been promoted in many countries as an organized community effort to meet the health, economic and social challenges of dental caries.