The treatment of seven children and adolescents with a tic disorder and concomitant attention-deficit hyperactivity disorder (ADHD) is reviewed. Symptoms of ADHD were treated successfully with clonidine; however, patients experienced persistent tics. The patients were treated with the adjunctive use of clonazepam. The addition of clonazepam resulted in a further decrease in tic frequency and severity without affecting the coexisting ADHD symptoms. These cases suggest that clonazepam may be a useful adjunctive pharmacological intervention in treating tics in children with comorbid ADHD.