A mobile unit for child and adolescent psychiatry is described that serves two counties with a combined population of 400 000. In both counties the unit is the third most frequently used outpatient service, providing 21% of all outpatient care in child and adolescent psychiatry in Marburg-Biedenkopf and 40% in Waldeck-Frankenberg. After the outpatient clinics this unit serves the largest number of patients from the lower social classes, in the case of psychotherapy the majority (54.1%). This unit also makes the largest number of home visits. On the whole, the mobile unit can be considered an effective means of providing mental health services in rural areas.