Martha Putallaz, PhD, is Professor of Psychology at Duke University, where she joined the faculty in 1983. Dr. Putallaz is a long-standing researcher in the field of children's social development and peer relationships. Most recently, she has been Principal Investigator of a comprehensive study of aggression and social rejection among middle childhood girls, funded by the National Institute of Mental Health. She is also a codirector of the Carolina Consortium on Human Development and the executive director of Duke's Talent Identification Program.

Karen L. Bierman, PhD, is Director of the Children, Youth, and Families Consortium and Distinguished Professor of Clinical Child Psychology at Pennsylvania State University. Her research has focused on understanding how peer relationships contribute to children's social-emotional development, social competence, and school adjustment. Currently, she is the director of the Pennsylvania site of the Fast Track project, a national, multisite prevention trial funded by the National Institute of Mental Health, with additional funding from the National Institute on Drug Abuse (NIDA) and the U.S. Department of Education. She is also coinvestigator of the newly funded PROSPER program, supported by NIDA, which involves the diffusion of empirically supported prevention programs to schools through the use of cooperative-extension-facilitated university-community partnerships.