Few empirical data address naturalistic outcomes of residential eating disorder (ED) treatment. Study aims were to evaluate course, effectiveness, and predictors of outcome in a residential treatment program. We evaluated 80 consecutively admitted female adolescents with the SCID-IV. Primary outcomes were treatment completion, subsequent readmission, clinical global impressions, and changes in body weight. Mean length of stay was 51 days, and 80% of patients were discharged according to treatment plans. Mean expected body weight (EBW) for AN patients increased from 80% to 91%. Patients reported significant improvements in ED symptoms, depression, and quality of life. Low admission %EBW and previous psychiatric hospitalizations were associated with premature termination. Overall, findings support that residential treatment is largely acceptable to patients, and that residential care may provide an opportunity for substantive therapeutic gains.