Since the United States and Canada could not resolve their contentious dispute on lumber trade, both countries approached the World Trade Organization to resolve this long-running disagreement. Each country filed three petitions covering (a) countervailing duties (CVD), (b) antidumping, and (c) material injury resulting from CVD and antidumping. This article briefly reviews the dispute, explains both countries' factual arguments submitted to the WTO, presents the WTO rulings on the three petitions, and discusses the economic implications of WTO findings.