This study replicated, in the subsequent academic year, teacher-reported prevalence rates for attention deficit/hyperactivity disorder (ADHD) based on DSM-IV. Teachers in grades K-5 in a Tennessee county (10 schools, 214 teachers, and 4323 children) completed questionnaires on all their students consisting of the DSM-IV symptoms for disruptive behavior disorders, except for eight conduct disorder symptoms, seven symptoms screening for anxiety or depression, ratings of performance, and questions about the presence of ADHD, stimulant medication treatment, and behavioral or academic problems. The prevalence rates were 16.1% for ADHD-all types, 8.8% for ADHD-inattentive type (AD), 2.6% for ADHD-hyperactive/impulsive type (HI), and 4.7% for ADHD-combined type and 6.8, 3.2, 0.6, and 2.9%, respectively, when impairment was taken into consideration. The rates of problems differed mostly between ADHD-AD and ADHD-HI (30% vs. 68%) for behavior and (56% vs. 16%) for academics. Few (11-33%) had an ADHD diagnosis or were treated with stimulant treatment (8-26%). DSM-IV criteria are likely to increase the prevalence but may better characterize the heterogeneity of this disorder.