All economic systems have ways in which they determine how much their total trade with the world will be, what commodities will make up that total, and the destinations and sources of those commodities (the geographic composition of exports and imports). In Western economies, which rely heavily on markets, the values of these variables summarize the outcome of a myriad of private decisions, with some influence of governments primarily through tariffs and quotas. In Eastern economies, which rely heavily on central planning, the government itself through its planners directly determines the value of those same variables.The concept of Most-Favored Nation (MFN) treatment evolved as a mechanism by which governments in market economies could agree mutually to limit interference in private decisions on trade, with the expected consequence being an increase in trade and welfare. When two market economy governments agree to accord MFN treatment to each other's commodities, it means (in its simplest form) that tariffs applied in each country to commodities imported from the other country shall be no higher than the lowest tariffs charged on imports of those commodities from any destination.