Summary: Attention-Deficit Hyperactivity Disorder (ADHD) is the most common pediatric neurobehavioral disorder with a prevalence of approximately 7%-10% in school-age children. ADHD significantly affects functioning throughout life including academic achievement, social and family relationships and occupational success, predisposing individuals to secondary psychopathology, substance use, justice system involvement and suicide. Fortunately, ADHD is treatable, most effectively with a combination of medication, behavioral therapy and school-based supports. Unfortunately, many children with ADHD go undiagnosed and untreated for years, and sometimes for life, putting those children most at risk for problematic outcomes.