The Economic Community of West African States (ECOWAS) was created by the Treaty of Lagos in Lagos, Nigeria, on 28 May 1975. It was created to promote economic trade, national cooperation, and monetary union, for growth and development throughout West Africa. Its four commissions deal with the following functions:
- Trading, immigration, monetary interaction
- Industry, natural resources, and agriculture
- Transportation and communications
- Social and cultural issues
There were 15 members initially: Benin, Côte d'Ivoire, Gambia, Ghana, Guinea, Guinea-Bissau, Liberia, Mali, Mauritania (left 2002), Niger, Nigeria, Senegal, Sierra Leone, Togo, and Burkina Faso (joined as Upper Volta). Cape Verde joined in 1977.
A revised treaty intended to accelerate integration of economic policy and improve political cooperation was signed on 24 July 1993. It sets out the goals of a common economic market, a single currency, the creation of a West African parliament, economic and social councils, and a court of justice.
The treaty also lays the burden of settling regional conflicts on the treaty members. To this end there is also a Mutual Defence Protocol: a non-standing army deployed in the region as ECOMOG.