As pressure increases for the demonstration of effective treatment for children with mental disorders, it is essential that the field has an understanding of the evidence base. To address this aim, the authors searched the published literature for effective interventions for children and adolescents and organized this review as follows: (1) prevention; (2) traditional forms of treatment, namely outpatient therapy, partial hospitalization, inpatient treatment, and psychopharmacology; (3) intensive comprehensive community-based interventions including case management, home-based treatment, therapeutic foster care, and therapeutic group homes; (4) crisis and support services; and (5) treatment for two prevalent disorders, major depressive disorder and attention-deficit hyperactivity disorder. Strong evidence was found for the treatment of attention-deficit hyperactivity disorder, depression, anxiety, and disruptive behavior disorders. Guidance from the field relevant to moving the evidence-based interventions into real-world clinical practice and further strengthening the research base will also need to address change in policy and clinical training.