Psychiatric disorders and psychological problems are common in patients with diabetes mellitus. There is a twofold increase in depression which is associated with suboptimal glycemic control and increased morbidity and mortality. Other psychiatric disorders with a higher incidence of diabetes mellitus are cognitive impairment, dementia, disturbed eating behavior, anxiety disorders, schizophrenia, bipolar disorders and borderline personality disorder. The coincidence of mental disorders and diabetes mellitus has unfavorable influences on metabolic control and micro- and macroangiopathic complications. Improvement of therapeutic outcome is a challenge in the modern health care system. The intentions behind this position paper are to rise awareness of this special set of problems, to intensify cooperation between involved health care providers and to reduce incidence of diabetes mellitus as well as morbidity and mortality from diabetes in this patient group.