The American Academy of Pediatrics' Committee on Quality Improvement, Subcommittee on Attention-Deficit/Hyperactivity Disorder, reviewed and analyzed the current literature for the purpose of developing an evidence-based clinical practice guideline for the treatment of the school-aged child with attention-deficit/hyperactivity disorder (ADHD). This review included several key reports, including an evidence review from the McMaster Evidence-Based Practice Center (supported by the Agency for Healthcare Research and Quality), a report from the Canadian Coordinating Office for Health Technology Assessment, the Multimodal Treatment for ADHD comparative clinical trial (supported by the National Institute of Mental Health), and supplemental reviews conducted by the subcommittee. These reviews provided substantial information about different treatments for ADHD and their efficacy in improving certain characteristics or outcomes for children with ADHD as well as adverse effects and benefits of multiple modes of treatment compared with single modes (eg, medication or behavior therapies alone). The reviews also compared the effects of different medications. Other evidence documents the long-term nature of ADHD in children and its classification as a chronic condition, meriting the application of general concepts of chronic-condition management, including an individual treatment plan with a focus on ongoing parent and child education, management, and monitoring. The evidence strongly supports the use of stimulant medications for treating the core symptoms of children with ADHD and, to a lesser degree, for improving functioning. Behavior therapy alone has only limited effect on symptoms or functioning of children with ADHD, although combining behavior therapy with medication seems to improve functioning and may decrease the amount of (stimulant) medication needed. Comparison among stimulants (mainly methylphenidate and amphetamines) did not indicate that 1 class outperformed the other.