In the past, preventive measures for psychoses have focused mainly on schizophrenic disorders. Bipolar disorders are often diagnosed and treated with a significant delay. The expansion of preventive measures for bipolar disorders aims at minimizing the substantial negative consequences associated with the disease. Some of the shared aspects of prevention in psychoses and bipolar disorders are that the first symptoms commonly appear during adolescence and early adulthood and that there is a symptomatic overlap between the disorders. To improve efforts to seek early help, public information about mental illness, low threshold services as well as cooperation between adult, child and adolescent psychiatry are needed for this target group. One differences is that psychotic symptoms play a minor role in bipolar disorders. Specific biological markers, such as disturbances of sleep and circadian rhythm and clinical characteristics, such as substance use and behavioral problems in childhood and youth supplement (subsyndromal) clinical symptoms in a multifactorial risk model. Besides severity and frequency of symptoms, specific periodic course patterns are crucial. Strategies of early intervention require a careful consideration of risks and benefits. Two aims should be distinguished: the improvement of current symptomatology and the prevention of conversion to bipolar disorder. Currently, studies evaluating risks and benefits of such interventions are first conducted. Expertise and resources for early recognition of psychoses and bipolar disorders should be pooled. Common standards are the basis for advancement and implementation of preventive strategies for bipolar disorders.