In international law and international relations, a protocol is a treaty or international agreement that supplements a previous treaty or international agreement. A protocol can amend the previous treaty, or add additional provisions. Parties to the earlier agreement are not required to adopt the protocol; sometimes this is made clearer by calling it an 'optional protocol', especially where many parties to the first agreement do not support the protocol. International law deals with the relationships between states, or between persons or entities in different states. ... International relations (IR) is an academic and public policy field, a branch of political science, dealing with the foreign policy of states within the international system, including the roles of international organizations, non-governmental organizations (NGOs), and multinational corporations (MNCs). ... A treaty is a binding agreement under international law concluded by subjects of international law, namely states and international organizations. ... A treaty is a binding agreement under international law concluded by subjects of international law, namely states and international organizations. ...

Some examples: the United Nations Framework Convention on Climate Change (UNFCCC) established a framework for the development of binding greenhouse gas emission limits, while the Kyoto Protocol contained the limits later agreed upon. UNFCCC logo. ... Kyoto Protocol Opened for signature December 11, 1997 at Kyoto, Japan Entered into force February 16, 2005. ...