There is a growing awareness that attention deficit hyperactivity disorder (ADHD) is a disorder that endures past adolescence into adulthood. What is now clear is that a significant number of people diagnosed with ADHD as children will continue to experience symptoms of inattention, overactivity and impulsivity as adults. In this article, the authors describe the main features of this condition and summarise the main pharmacological and psychosocial treatments that are available to support children, young people, and adults with ADHD.