For many years, under U.S. tariff laws, U.S. footwear companies have sent items overseas for partial production and brought them back to the U.S. for finishing, only paying duties on the value added by the overseas work. China has historically been the main source of work for the U.S. and remains the world's largest shoe producer and the main source of footwear imported by the U.S. Under the World Trade Organization (WTO) agreement of 1995, apparel and textile quotas are being gradually eliminated by2007, and firms are responding by cutting down on domestic manufacturing. For example, NIKE markets shoes but is not involved in manufacturing. The danger of outsourcing is that manufacturers have less control over overseas factories, some of which badly exploit workers.