Attention-deficit/hyperactivity disorder (ADHD) is the most common neurobehavioral disorder presenting for treatment in children and adolescents, and is a growing presentation in adults. However, few mental health professionals currently feel comfortable diagnosing ADHD across the lifespan; and even fewer are comfortable with their knowledge base on treatment strategies for these patients. Little is known by mental health professionals about the long-term effects of chronic treatment on the course and associated problems of ADHD despite an expanding international literature. This session will provide an update on the course, comorbidity, and long-term treatment of ADHD.