Attention deficit hyperactivity disorder (ADHD) is one of the most common mental disorders among children. Children with ADHD frequently lack organizational, time management, and planning skills. These deficits can cause impaired functioning in multiple settings, including home, school, and peer relationships. Advancements in treatment options for these deficits, however, have been minimal. Previous research has indicated that organizational skills training (OST) is an effective intervention for improving organizational skills in children with ADHD. Its effectiveness relative to other available treatments is unknown. This study will compare the effectiveness of OST with that of contingency management (CM) and a waitlist condition in improving organizational, time management, and planning skills deficits in children with ADHD.