As prescriptions for stimulant medication to treat ADHD have increased, so have concerns about the nonmedical use and diversion of stimulant medication, especially among college students. There is also growing concern about young adults feigning ADHD in order to receive a prescription for stimulant medication. This paper summarizes recent research on the nonmedical use and diversion of stimulant medication with a focus on the prevalence of these behaviors, motivations for nonmedical use, factors associated with nonmedical use, and the consequences of such use. Research on the medical misuse of prescribed medication and malingering to obtain a diagnosis of ADHD is also discussed.