No lawyer or business operating in North America can escape the significance of the USMCA. This Nutshell introduces students, lawyers, government officials, and businesspersons to the law and economics of North American free trade. It first examines the basic question: Why trade at all? The origins, rules, operation, and impact of the Canada-U.S. FTA (1989) and the NAFTA (1994), USMCA's influential predecessors, follow. Notable trade, intellectual property and foreign investment developments under the 2020 USMCA agreement, and their impacts upon business, are specifically explored. In preparing this Nutshell, we have attempted to address the interests not only of North Americans, but also the many persons and businesses located outside the region who seek to take advantage of the USMCA.