Objective Cooperation, job satisfaction, and burn out risk are indicators of sustainability in mental health services. Thus they were assessed among registered medical specialists in outpatient mental health care in Germany. Method A postal survey consisting of three questionnaires about cooperation, job satisfaction, and burnout was carried out among all registered medical specialists in outpatient mental health care in Germany (n = 4,430). Results 14.1 % (n = 626) of the specialists responded to the survey. Quality and quantity of cooperation regarding mental health care services were rated diverse, job satisfaction was assessed medium to high, and burnout risk was low to medium. Higher job satisfaction correlated with good quality of cooperation, fewer years of practice, fewer patients’ chronically ill, more patients who as well seek psychotherapy, and less time spent on cooperation. Low burn out risk correlated with good quality of cooperation, higher age, single practice setting and a higher amount of patients who as well seek psychotherapy. Conclusion Quality and quantity of cooperation in outpatient mental health care - especially regarding community mental health care institutions - should be fostered. Aspects to be considered to reinforce job satisfaction and minimize burn out risk are age, years of practice, quality and quantity of cooperation, practice setting, and the mixture of patients.