The article establishes methods by which to estimate U.S. commercial firearms demand and supply. For the first time, this includes the number of used firearms resold via federally licensed retailers. For 2010, for example, total unit sales are estimated at 9.8 million firearms (pistols, revolvers, rifles, and shotguns), about 1.5 million of which were resales of used weapons. The article also shows rising firearms imports in general as well as a growing market share of non U.S. brands produced within the United States, especially in the pistol segment of the firearms market.