"The World Trade Organization (WTO) is an international organization that administers the trade rules and agreements negotiated by its 164 members to eliminate trade barriers and create nondiscriminatory rules to govern trade. It also serves as an important forum for resolving trade disputes. The United States was a major force behind the establishment of the WTO in 1995 and the rules and agreements that resulted from the Uruguay Round of multilateral trade negotiations (1986-1994). The WTO encompassed and expanded on the commitments and institutional functions of the General Agreement on Tariffs and Trade (GATT), which was established in 1947 by the United States and 22 other nations. Through the GATT and WTO, the United States and other countries sought to establish a more open, rules-based trading system in the postwar era, with the goal of fostering international economic cooperation, stability,and prosperity worldwide. Today, the vast majority of world trade, approximately 98%, takes place among WTO members."
CRS Report for Congress, R45417
Congressional Research Service: https://crsreports.congress.gov/