The Economic Community of West African States (ECOWAS) is a regional group of 15 West African countries.
Founded on 28 May 1975, with the signing of the Treaty of Lagos, its mission is to promote economic integration across the region and achieve "collective self-sufficiency" for its member states by creating a single large trading bloc through an economic and trading union.
It also serves as a peacekeeping force in the region. The organization operates officially in three languages - English, French, and Portuguese.
In 1976 Cape Verde joined ECOWAS, and in December 2000 Mauritania withdrew, having announced its intention to do so in December 1999.