The articles in this collection focus on the intersection of competition law and class actions. They consider the role that class actions can play in achieving an optimally competitive market for goods and services and in providing compensation for those who have suffered as a result of anticompetitive conduct. They examine key issues such as the appropriate test for class action certification and acceptable methodologies for calculating damages, and in doing so, they bring to bear the views of legal academics, economists, and experienced practising lawyers. This book grew out of a symposium held at the Faculty of Law at the University of Western Ontario in late March 2005. The symposium brought together Canadian academics working in either the competition or class action field, practitioners involved in competition class action cases, judges who had heard some of these cases, and American academics who contributed a valuable comparative law perspective. The speakers each contributed an article to this collection, as did many of the commentators.