The following article presents aspects of the field of psychosocial medicine in Germany from the perspective of health services research. First, the tasks and topics of health services research are listed. The identification and appropriate treatment of people with mental disorders is one of the core themes of psychosocial health care; therefore, a brief overview of research results on the epidemiology of mental disorders is first presented. The primary focus of this article is then to provide a description and analysis of the structures of psychosocial care in inpatient and outpatient settings. Research findings concerning treatment processes and the result of these processes are additionally presented. The findings show that there is still a considerable lack of research results regarding the treatment of patients with mental disorders, as is also the case in other health care areas. An important empirical basis for rationally founded treatment planning in this area is thus lacking.