Approximately one-half of children medicated for attention-deficit hyperactivity disorder (ADHD) will continue to experience sufficient impairment during adolescence to warrant the continuation of their treatment; a smaller number of people with ADHD may require treatment for the first time during adolescence. The academic and social demands of adolescence can exaggerate the impairment caused by attentional problems, as adolescents, more so than children, have activities in the afternoon and evening that will tax their attentional abilities. Stimulant and nonstimulant medications are likely to be as effective for adolescent patients as they are for younger children, provided treatment adherence is satisfactory. Long-acting medications are preferred over immediate-release compounds as they provide better coverage of symptoms throughout the day. Patterns of comorbidity with ADHD change from childhood to adolescence and may require a shift in treatment strategy. The choice of time to discontinue treatment should be a decision shared by the clinician and the patient. A negotiated trial of time off treatment followed by a review of the patient's symptoms can avert premature discontinuation of treatment.