Mercosur, MEHR koh soor, is an association of several South American countries that work to increase trade among themselves. Argentina, Brazil, Paraguay, and Uruguay founded Mercosur in 1991. Venezuela became a full member in 2006. Associate members include Bolivia, Chile, Colombia, Ecuador, and Peru. Today, Mercosur is one of the world's largest trade blocs. Its name in Spanish is Mercado Comun del Sur (Southern Common Market). In Portuguese, the language of Brazil, the group is known as Mercado Comum do Sul (Mercosul). Headquarters are in Montevideo, Uruguay.