Requests for the assessment and treatment of attention-deficit/hyperactivity disorder (ADHD) among adult patients are on the rise. The findings from longitudinal research indicate that clinically significant symptoms persist into adulthood for many children diagnosed with ADHD. Many other patients' symptoms are not identified until they are in active treatment for other complaints in adulthood. Thus, psychotherapists are increasingly likely to encounter adult patients with ADHD-related issues. However, the same core symptoms of inattention, impulsivity, and hyperactivity that create functional problems in patients' lives also interfere with the effectiveness of psychotherapy. The aim of this article is to summarize the accumulated clinical and empirical wisdom about how to effectively adapt psychotherapy to meet the needs of adult patients with ADHD. Attention-deficit/hyperactivity disorder (ADHD) is a common neurobehavioral disorder of childhood that has wide-ranging effects on behavior, learning and cognition, and emotional functioning (Barkley, 1998; Brown, 2000; Wender, 2000). It is estimated that ADHD affects about 3-5% of school-age children in the United States (American Psychiatric Association [APA], 2000). Barkley (1998) summarized prevalence studies of ADHD that used established diagnostic criteria for children and adolescents. The prevalence rates ranged from 2% to 9.5% (M ϭ 4.9%) of children and adolescents when using DSM-III criteria (APA, 1980) and 1.4% to 13.3% (M ϭ 5.9%) when using adults' ratings of DSM-III-R criteria (APA, 1987). Reviews of international samples show similar prevalence rates of ADHD in children in other countries, indicating that ADHD is not simply an American disorder (Barkley, 1998; Faraone, Sergeant, Gillberg, & Biederman, 2003), though diversity issues remain understudied (Gingerich, Turnock, Litfin, & Rosén, 1998). The prevalence of ADHD in adults falls between 4 and 5%, on the basis of surveys of nonclinical samples of college students and of adults applying for their driver's licenses (Bark