Abstract For many psychiatric conditions outcomes of standard care still fall short of outcomes that are possible according to research literature. One of the major reasons is patient׳s non-adherence to long-term medication. We performed a mirror image interventional study involving patients suffering from affective (N=219) or psychotic disorders (N=210) who participated in an integrated care program focusing on treatment adherence. The main outcome variable was the number of inpatients days during the integrated care program compared to the time before the program. The integrated care project studied showed a drop of inpatient days of approx. 75% within the 18-months observation period for both groups. In the affective (psychotic) sample inpatients days dropped from M=47.1 days (M=62.2 days) in the 18 months before the program to M=10.8 days (M=15.3 days) during the adherence program. Patients with affective disorders additionally profited with regard to symptom reduction, quality of life and self-reported adherence. Thus, a complex intervention addressing frequent weaknesses of routine psychiatric outpatient care and focussing on adherence and linking up outpatient services is effective with regard to the reduction of inpatient days for patients with affective and patients with schizophrenic disorders.