Instrument by which nation-states and international organizations regulate matters of concern.
They are governed by international law , and their purposes include the development and codification of international law, the creation of international bodies, and the resolution of actual and potential international conflict. The most comprehensive agreement is a treaty ; others, including conventions (e.g., the Geneva Conventions ), charters (e.g., the UN charter), and pacts (e.g., the Kellogg-Briand Pact ), are less formal and rely primarily on goodwill. Agreements may be negotiated between states, between an organization and a state, between organizations, or between any of those and a nongovernmental organization .