Katarzyna Chawarska, PhD, is Assistant Professor at the Yale Child Study Center, Yale University School of Medicine, where she is also Director of the Developmental Disabilities Clinic for Infants and Toddlers. Dr. Chawarska's research focuses on early expression of ASD and on experimental studies of face and gaze processing in infants and toddlers. nbsp; Ami Klin, PhD, is the Harris Associate Professor of Child Psychology and Psychiatry at the Yale Child Study Center. He directs the Autism Program at Yale, which is one of the National Institutes of Health's Autism Centers of Excellence. Dr. Klin’s primary research activities focus on the social mind and the social brain, and on various aspects of autism from infancy through adulthood. He is the editor or coeditor of several books and special issues of professional journals. nbsp; Fred R. Volkmar, MD, is the Irving B. Harris Professor of Child Psychiatry, Pediatrics, and Psychology and Director of the Yale Child Study Center. He is also the Chief of Child Psychiatry at Yale–New Haven Hospital. Dr. Volkmar was the primary author of the American Psychiatric Association’s DSM-IV autism and Pervasive Developmental Disorders section. He is the author, coauthor, or coeditor of several hundred scientific papers and chapters and a number of books, and is Editor-in-Chief of theJournal of Autism and Developmental Disorders.