The ability to make decisions impacting international affairs can be a thorny subject for a federal state like Canada. Provinces wield considerable constitutionally assigned powers, but do those extend to Canada's dealings with other nations? How is power over foreign affairs defined within the law? Foreign Affairs in the Canadian Constitution breaks new ground with a rigorous exploration of these questions. Scott Fairley explores federal-provincial confrontations over foreign affairs, beginning with the free-trade debate of the 1980s and encompassing issues such as Quebec's assertion of its capacity to enter into treaties in areas of supposedly exclusive provincial authority. He provides the backdrop to these controversies, tracing Canada's evolution from self-governing semi-colonial status in 1867 to the autonomous nation-state it is today, and offers comparative analyses of legal approaches in other federal states, such as Australia and the United States. Scott Fairley proposes that the weight of history, constitutional evolution, governmental practice, and judicial interpretation have established foreign affairs as a constitutionally supported and integrated field of federal jurisdiction. This meticulously argued conclusion accords with basic principles of federalism while allowing us a better understanding of Canada as a unified nation-state within the community of nations.