UC Irvine has a long and successful history as one of the nation’s foremost experts in the treatment of children with behavior disorders. In 1994, the UC Irvine Child Development Center, under the direction of founder Dr. James Swanson, was selected by the National Institutes of Mental Health to participate in the Multimodal Treatment of ADHD (MTA) Study (The MTA Cooperative Group, 1999), a multi-site, longitudinal treatment study. Now in its 20th year of follow-up funding, the MTA Study is the largest multi-site longitudinal study of pediatric mental health to date examining the treatment efficacy of pharmacological, psychosocial, and combined treatments for ADHD. In 2000, the UC Irvine was selected by the National Institutes of Mental Health to participate in the Preschoolers with ADHD Treatment Study (PATS; Kollins et al., 2006), implementing a two-year treatment with a five-year longitudinal follow up examining the safety and efficacy of methylphenidate treatment in preschool-aged children at-risk for ADHD. Both of these studies (MTA and PATS) helped to establish the UC Irvine Child Development Center School as one of the foremost national and international authorities on the careful identification, diagnosis, and intervention of ADHD.