लेखक: Margaret Kerr

Rutger C.M.E. Engels, Ph.D., is Professor in Family Psychology at the Behavioural Science Institute, Radboud University Nijmegen, the Netherlands since 2001. He obtained his Ph.D. at the Department of Medical Sociology, Maastricht University in 1998. Since then he has worked for three years as a post-doc and assistant professor at the department of child and Adolescent Studies, Utrecht University. Currently, he is involved in fundamental research on the link between (social0environmental influences on adolescent and young adult substance use and delinquency. Margaret Kerr is Professor of Psychology at Orebro University, Sweden, and Co-director of the Center for Developmental Research. She earned her Ph.D. at Cornell University, U.S.A., and then completed a post-doctoral research fellowship with Richard Tremblay at the University of Montreal, Canada. She is an associate editor of the Journal of research on Adolescence. Her research focuses on internal and external adjustment in adolescents and its role in the life course. Her current research interests include adolescents choices of developmental contexts and parent-child relationships and their role in the development of delinquency. Hakan Stattin is Professor of Psychology at Uppsala and Orebro Universities, Sweden. He earned his Ph.D. at Stockholm University and has served as President of the European Association for Research on Adolescence and associates editor for the British Journal of Developmental Psychology. he is probably best known for his research in three areas: delinquency development, pubertal maturation in adolescent girls, and parental monitoring. His works include an authored book(with David Magnusson in 1990), Pubertal Maturation in Female Development. In addition to his continued basic research in these areas, he is conducting prevention trials to reduce alcohol drinking and delinquency among adolescents.