FRED R. VOLKMAR, MD, is the Irving B. Harris Professor of Child Psychiatry, Pediatrics and Psychology at Yale University School of Medicine, and is the primary author of the American Psychiatric Associations DSM-IV section on Autism and Pervasive Developmental Disorders. He is also the Dorothy Goodwin Professor of Special Education at Southern Connecticut State University. LISA A. WIESNER, MD, is a pediatrician, now retired, and previously a Clinical Assistant Professor, Department of Pediatrics, Yale University School of Medicine, New Haven, CT.