Robert Lee Burgess (Ph.D., Washington University in St. Louis, 1969) is Professor of Human Development at the Pennsylvania State University. He has degrees in anthropology, psychology, and sociology. He has published numerous articles in journals and chapters in books dealing with such topics as theory construction, the development of criminal behavior and illicit drug use, cooperation and competition in children's groups, the development and consequences of power differences in dyads involved in exchange relationships, and the role of imitation in retarded children. He is also co-author (with Don Bushell, Jr.) of Behavioral Sociology: The Experimental Analysis of Social Process and (with… Ted L. Huston) of Social Exchange in Developing Relationships. Drawing upon research methods developed by primatologists, he conducted one of the first observational studies of abusive and neglectful families in their own homes. Recently, he has published articles examining the convergence of evolutionary biology and behavior genetics for understanding human development.