The relevance of family interactions in the course of affective disorders has been well described. In contrast to the situation regarding schizophrenic disorders, there are few systematic concepts for involvement of the relatives of patients with affective disorders in treatment. The goal of this study was the development and evaluation of a standardised psychoeducational treatment programme. We determined the number and characteristics of relatives accepting the offer of such a group. Relatives of almost half of 55 patients with major depression and a bipolar disorder participated in the group. Relatives of male patients were more likely to take part than relatives of female patients. Relatives of patients with a bipolar disorder were more likely to take part than relatives of patients with unipolar depression. The patients whose relatives attended the group showed a more favourable understanding of the illness and more knowledge about affective disorders, but on the other hand, felt themselves to be more strongly criticised by their relatives and had less social support than the other patients. These results emphasise the importance of differential family-focused treatment modalities in affective disorders.