A Practice Note providing an overview of foreign-trade zones (FTZs), which are the US equivalent of sites known internationally as free-trade zones. This Note discusses the origin and purpose of the FTZ program, the roles of the two administering agencies, the US Foreign-Trade Zones Board and US Customs and Border Protection (CBP), permissible activities in an FTZ, the potential financial benefits of using an FTZ, including the deferral, reduction, or elimination of customs duty payments, and enforcement of FTZ program requirements by the FTZ Board and CBP.