Anorexia nervosa is a serious condition associated with high mortality. Incidence is highest for female adolescents, and prevalence data highlight a pressing unmet need for treatment. While there is evidence that adolescent-onset anorexia has relatively high rates of eventual recovery, the illness is often protracted, and even after recovery from the eating disorder there is an ongoing vulnerability to psychosocial problems in later life. Family therapy for anorexia in adolescence has evolved from a generic systemic treatment into an eating disorder-specific format (family therapy for anorexia nervosa), and this approach has been evidenced as an effective treatment. Individual treatments, including cognitive behavioral therapy, also have some evidence of effectiveness. Most adolescents can be effectively and safely managed as outpatients. Day-patient treatment holds promise as an alternative to inpatient treatment or as an intensive program following a brief medical admission. Evidence is emerging of advantages in detecting and treating adolescent anorexia nervosa in specialist community-based child and adolescent eating-disorder services accessible directly from primary care. Limitations and future directions for modern treatment are considered.