Evaluation, diagnosis, and treatment of children with complex multiple psychiatric comorbidities and out-of-control behaviors is a daunting task. The variability of clinical course, influences of psychosocial environment, confounding clinical needs of multiple comorbidities, and lack of published treatment studies are just the beginning of the challenges faced by clinicians. At this time the best established treatment approaches for disruptive behavior in children with complex multiple psychiatric comorbidities include parent management training and pharmacotherapy, and psychotherapy targeted at specific psychiatric disorders. In addition, parent psycho-education and appropriate educational modifications are frequent components of comprehensive treatment plans. This Workshop presents an ecologically-based, comprehensive model of in-home treatment that shows robust, data-supported evidence of clinical effectiveness with this population.