Research is needed to further examine the role of treatment alliance or engagement among child and adolescent patients in inpatient psychiatric settings. In this study, 72 newly admitted patients on an inpatient adolescent psychiatric unit completed measures of symptom severity and treatment alliance. Female patients showed greater symptom severity at both admission and discharge. Residualized gain score analysis showed that male gender predicted greater symptom reduction. Treatment alliance also predicted greater symptom reduction, but only among women. These results suggest that alliance or engagement with acute inpatient psychiatric services may play a more important role among women than men in predicting symptomatic change in severely disturbed adolescents. Copyright © 2016 John Wiley & Sons, Ltd.