Debra J. Pepler is a distinguished research professor of psychology at York University and a senior associate scientist at the Hospital for Sick Children. Her research is on aggression and victimization among children and adolescents. With Wendy Craig, she leads a national network, PREVNet (Promoting Relationships and Eliminating Violence Network), to promote safe and healthy relationships for all Canadian children and youth (www.prevnet.ca).

H. Bruce Ferguson is the director of the Community Health Systems Resource Group at the Hospital for Sick Children and a professor in the departments of Psychiatry and Psychology and the Dalla Lana School of Public Health at the University of Toronto.