Malcolm W. Klein is Emeritus Professor at University of Southern California. Winner of the Sutherland, Wolfgang, Tappan and McGee Awards in criminology, he has been consultant to scores of public and private enforcement and social service agencies, and served as expert witness in over one hundred criminal gang cases. Cheryl L. Maxson is Associate Professor in the Department of Criminology, Law and Society at the University of California's Irvine Campus. She has directed research on regional, national and international gang issues and studies juvenile delinquency and violence, street gang...