International studies have demonstrated that the prevalence rates of psychiatric disorders in children and adolescents in population samples vary between 8 and 23 %. Our own school-based study in Germany in a selection-free sample revealed a prevalence of 12.7% in the age-group between 6 and 18. The need for treatment according to international studies is at least 5 %. Over the past 30 years, increasing figures have been described regarding aggressive behavior, alcohol and drug addiction, delinquency, depression, suicidal behavior, obesity, and eating disorders. This underlines the importance of prevention, subdivided in universal prevention addressed to a complete population, and targeted prevention (selective and indicated prevention aiming at groups with increased risk or already identified high-risk groups).

After the discussion of biological, psychological, and psychosocial risk factors and markers of resilience, an overview is given of some established prevention programmes for psychopathological disorders in children and adolescents, followed by the results of three prevention programmes on school drop-out carried out within the WPA Presidential Programme on Child Mental Health in Alexandria/Egypt, Nishnij Novgorod/Russia, and Porto Alegre/Brazil.

A comparison was made between intervention schools where defined interventions had taken place and control schools where only information was given and no formal interventions had been carried out.

In all three locations, the preventive interventions were successful: The school drop-out rate could be significantly reduced within the course of one year. As school drop-out is associated with many other disorders and disadvantages, this is an encouraging result.