The ECOWAS Monitoring Group (ECOMOG) is a multi-national armed force tasked by ECOWAS in 1990 to intervene in the Liberian Civil War. It's role has since expanded to include initiatives for regional security and peace-keeping, with interventions to control conflict in Sierra Leone and Guinea-Bissau.

Nigeria provides the largest component (both of armed forces and financial resources); Ghana, Guinea, Sierra Leone and Gambia also contribute smaller units.