Peter Carrington is Professor of Sociology at the University of Waterloo. His main teaching and research interests are in the criminal and juvenile justice systems, social networks, and research methods and statistics. He has published articles in the Canadian Journal of Criminology and Criminal Justice, American Journal of Psychiatry, Journal of Mathematical Sociology, and Social Networks. He has most recently been involved in several evaluation studies for the Department of Justice Canada. He is currently doing research on police discretion, criminal and delinquent careers and networks, and