The peacekeeping mission in El Salvador, Unusal, helped the country through a period of transition after 10 years of civil war, in which more than 75,000 people were killed. First established to monitor a ceasefire and verify the implementation of the peace agreement, Unusal went on to oversee free elections in 1994.
The UN observers also supervised the creation of a new police force, and oversaw the reform and reduction of the armed forces. Under Unusal direction, a large-scale decommissioning of weapons took place, in an unprecedented move for peacekeeping.
The combatants agreed to hand over their weapons to UN observers over a two-year period.
The El Salvador government has since been criticised for slow progress in implementing parts of the peace accords, especially in human rights and land reform.