Foreign exchange controls are various forms of controls imposed by a government on the purchase/sale of foreign currencies by residents or on the purchase/sale of local currency by nonresidents.Common foreign exchange controls include:Banning the use of foreign currency within the countryBanning locals from possessing foreign currencyRestricting currency exchange to government-approved exchangersFixed exchange ratesRestrictions on the amount of currency that may be imported or exportedCountries with foreign exchange controls are also known as "Article 14 countries," after the provision in the International Monetary Fund agreement allowing exchange controls for transitional economies. Such controls used to be common in most countries, particularly poorer ones, until the 1990s when free trade...