Young drivers with attention deficit/hyperactivity disorder (ADHD), because of their inattention and impulsivity, have more vehicular collisions, citations, and related injuries than drivers without ADHD.1 In laboratory studies, methylphenidate has improved simulated driving in this population.2 However, it is unknown whether long-acting methylphenidate improves routine driving while youth negotiate cell phones, music systems, teenaged passengers, and rushed schedules.