The purpose of this prospective survey, conducted over a two years period, was to study the use of psychoactive drugs among six year-old children in the Bas-Rhin administrative "département", of eastern France. The factors analysed were family environment, after-school time, the child's sleep, the locality where the child lived and the drugs used. The child was examined by school doctors, in the presence of the parents, at the compulsory consultation at the start of first-year infant school. The study was exhaustive. Of the 11,274 children examined, 12.1% used a psychoactive drug, although only 1% were considered by their parents to be suffering from insomnia. Of the children using drugs, 32% had used them for more than a year, 24% for more than two years and 11% for more than three years. Consumption was also shown to vary greatly between different localities; in some areas the proportion of children using drugs was more than 50%.