This efficacy study compares an adjuvant specific psychotherapy and an active control intervention for Bipolar Disorder under mood stabilizer to prevent relapse an maintain remission. Patients should be in their early (18-30 yr.) phase of illness without having suffered of to many affective episodes (below 6), already. In addition, psychological, social, and neurobiological mediators and moderators well be identified.

There is still a lack of controlled outcome and follow-up studies about the role of adjuvant psychotherapy in Bipolar Disorder. By treating older subjects having suffered of multiple affective episodes, the potential benefit of psychotherapy to prevent relapse and help to adjust to this chronic illness might be underestimated. In addition, the investigators have no knowledge of mechanism (mediators) of positive changes by successful psychotherapy and of subjects with good outcome of adjuvant psychotherapy (moderators, indicators, predictors). Possible mediators and moderators can be sociodemographic, psychological (cognitive, interactional), and/or biological (neuronal, genetic). The planned study will address all three areas of questions. In a multi-center study, 300 younger subjects suffering of a Bipolar Disorder will be included and provide with one of two treatments in addition to stable medication. Moderators and mediators are selected on promising preliminary results and based on a psycho-biological understanding of Bipolar Disorder.

Inclusion Criteria:

• Bipolar I and Bipolar II Disorder,
• 18 to 55 years of age,
• giving informed consent to assessment, treatment, and randomization,
• currently remitted (for at least 4 weeks) and taking medication,
• less than 6 previous affective episodes

Exclusion Criteria:

• currently symptomatic (depressed, manic, hypomanic),
• suicidal,
• not taking medication,
• schizo-affective, schizophrenic, borderline personality disorder,
• not giving or withdrawing consent