According to the Canadian Constitution and jurisprudence, the federal government has full powers with respect to treaty-making and international trade responsibility. However, the provinces have become increasingly important players on trade issues. Trade negotiations increasingly affect areas under provincial jurisdiction and the federal government cannot impose treaties in these areas on the provinces. This article compares provincial involvement in three important negotiations: the Canada-United States Free Trade Agreement (FTA), the CanadaEuropean Union Comprehensive Economic and Trade Agreement (CETA), and the Trans-Pacific Partnership (TPP).