The number of publications on attention deficit hyperactivity disorder (ADHD) has increased sharply over the last 10 years, with more than 700 likely for 2012. Consequently, it is difficult to stay apprised of this literature. This issue of Neurotherapeutics includes 12 comprehensive reviews of topics related to ADHD.ADHD is the most common childhood behavioral disorder and one of the more common adult psychiatric disorders. Traditional therapeutics for ADHD include behavioral therapy and pharmacologic intervention. These approaches have been available for decades; however, therapies have evolved and expanded with better understanding of the disorder. This includes a better understanding of the role of dopamine and norepinephrine and how this new knowledge can guide the development of novel pharmacological agents. Better recognition of subpopulations of the disorder, the presence of co-morbidity (e.g., sleep disturbance and autism spectrum disorders), and need to address the disorder throughout the life span have helped refine the diagnostic process. The search for improved treatments for ADHD continues, as a significant portion of the ADHD population does not respond, or responds sub-optimally, to currently available therapy. Concerns about drug side effects have fostered an interest in identifying new and alternative treatment options.The current issue reviews new approaches that range from preventative interventions that minimize the development of the disorder to the potential for treatment based on electrical brain response. Similarly, the role of environmental impact, such as food and food dyes, on behavior associated with ADHD, is addressed. Also critically reviewed are current conceptualizations of the disorder and potential new targets for treatment. The latter articles include discussion of prevalence of the disorder and subtypes, the role of variability in response times in ADHD, cognitive training approaches for targeting reward-related and cognitive impairments, among others.Willcutt [1] (this issue) report the largest meta-analysis to date on the prevalence of ADHD, along with related analyses of a large population-based sample. Prevalence varied according to diagnostic methodology, but using a bestestimate procedure and strict DSM-IV diagnostic criteria, the overall incidence of ADHD was estimated to be 5.9 %, and similar across countries and regions. Tests of changes proposed for diagnosing ADHD in DSM-V found little effect for relaxing the age of onset criterion or allowing co-morbid psychotic or pervasive developmental disorders. In contrast to the wealth of data on children, much less is known about ADHD in adults. Green and Rabiner [2] (this issue) contribute a qualitative discussion of the small volume of literature available on ADHD in college students. Among the difficulties with diagnosing and treating ADHD in college students his group noted are the high rates of malingering in order to obtain prescription medication, and the frequency of diversion and misuse of medication.Children with ...