A nongovernmental organization (NGO) is a group or association of individuals, organizations, or states acting for charitable, humanitarian, economic, or political purposes in the space between individuals and governments, in the absence of a responsible governing body at the local or international level, or on the margins between nation-states. Although much of the social science literature presumes that the NGO is a 19th-century Western invention, world history shows otherwise. In the last century, the relationship of NGOs to warfare and conflict has changed. Currently, the NGO is a factor in the prosecution of war, in policy to prevent conflict, and in humanitarian aid for displaced persons as a result of war.

This entry begins by further defining NGOs and describing the history of the concept. Next, ...