The present paper compares course and outcome of adolescent anorexia nervosa to that of adult onset forms. In recent studies earlier onset of anorexia nervosa was associated with higher recovery rates and a lower mortality, although even in adolescent patients anorexia nervosa takes a prolonged course. A chronic eating disorder bears a high risk of other comorbid psychiatric or personality disorders. The most prevalent disturbances were anxiety and affective disorders and anxious–fearful–obsessive personality disorders, respectively. Patients who substantially overcame their eating disorder did not differ from normal controls in respect to psychosocial functioning, e.g. family relationships, partnership and occupational status. These results should encourage us to treat the eating disorder vigorously.