Due to its long-lasting effects, the consumption of tobacco, alcohol and drugs is one of the central topics of prevention and health promotion in childhood and adolescence. The data from the German Health Interview and Examination Survey for Children and Adolescents (KiGGS) show that in Germany today 20.5 % of 11-17-year-old boys and 20.3 % of girls the same age smoke. More than one quarter of adolescents who do not smoke themselves are exposed to cigarette smoke several times a week; around one fifth are even exposed to it almost every day. In the case of alcohol, 64.8 % of boys and 63.8 % of girls have drunk it before. Around one third of boys and one quarter of girls indicated that they currently consumed alcohol at least once a week. In the last 12 months before the survey 9.2 % of the boys and 6.2 % of the girls had taken hashish or marijuana. Other drugs such as Ecstasy, amphetamines or speed had been consumed by less than 1 % of the adolescents. The use of psychoactive substances rises markedly as children get older and is thus the most widespread among 16-17-year-olds. Adolescents of low social status smoke more frequently; in the case of alcohol and drug consumption, however, no significant status-specific differences are observed. There is also a raised prevalence of smoking among boys and girls who attend a secondary school and live in the states of the former GDR. The results emphasise the need for an addiction prevention programme which should include intervention to prevent children taking up substance use, as well as withdrawal treatment.