Overview
The traditional classifications of organizations that play a part in international law include governments, intergovernmental organizations (IGOs), and nongovernmental organizations (NGOs). Intergovernmental Organizations (IGOs) are created by states through multilateral treaties that act like a constitution in that the states parties are consenting to be bound by the treaty that sets up the agencies, functions, and purposes of the organization. IGOs are involved in treaty making but they also publish other documents that those researching International law may be interested in.
An IGO has international legal status that may include privileges, immunities, rights and duties that are in turn based upon its founding charter or statute. As such, an IGO can enter into agreements with other IGOs or with states. An IGO usually has a legislative body which creates legal acts (decisions, resolutions, directives, etc.) which may bind the IGO and its member states under international law. Most of these legislative acts do not supersede national law (except in the EU). An IGO may have a dispute resolution mechanism or body which is empowered to resolve disputes among its member states. The IGO may have an executive body (such as a secretariat) which facilitates the operations of the IGO.
The best known IGO is probably the UN but there are thousands. Many IGOs issue publications and documents that may be of interest to the legal researcher: founding documents (treaties, charters, statutes), treaties where the IGO is a party, legal acts, proceedings, documents issued by the IGO's legislative body, and decisions of the IGO's adjudicative body.
The above diagram illustrates four countries (A, B, C & D) forming an IGO through a multilateral treaty.
