Jennifer E. Lansford, PhD, is Research Scientist at the Duke University Center for Child and Family Policy. Her research focuses on the development of aggression and other behavior problems in youth, with an emphasis on how family and peer contexts contribute to or protect against these outcomes. Dr. Lansford examines how experiences with parents (e.g., discipline, physical abuse, divorce) and peers (e.g., rejection, friendships) affect the development of children’s behavior problems, how influence operates in adolescent peer groups, and how cultural contexts moderate links between parents’ discipline strategies and children’s behavior problems. nbsp; Kirby Deater-Deckard,… PhD, is Professor and Director of Graduate Programs in the Department of Psychology at the Virginia Polytechnic Institute and State University. In his research, he examines genetic and environmental influences on child and adolescent social-emotional and cognitive development, with particular emphasis on parenting and cultural influences. Dr. Deater-Deckard has published several papers, book chapters, and booksnbsp;in the areas of developmental psychology and child development. He is Joint Editor of theJournal of Child Psychology and Psychiatry. nbsp; Marc H. Bornstein, PhD, is Senior Investigator and Head of Child and Family Research at the National Institute of Child Health and Human Development. He was a Guggenheim Foundation Fellow and has received awards from the National Institutes of Health and the American Psychological Association, among others. Dr. Bornstein is coauthor ofDevelopment in Infancy,now in its fifth edition, as well as numerous other volumes. He is Editor Emeritus ofChild Developmentand Founding Editor ofParenting: Science and Practice.