Sources of International Law

International law is a collection of complex and developing rules, which governs the relations between nations.  International law provides guidelines to sovereign states and international organizations and some individuals.  The range of subjects directly concerned with international law has widened considerably, moving beyond the questions of war, peace, and diplomacy to include human rights, trade issues, space law, and international organizations.

Sources of international law are the materials and processes out of which the rules and principles regulating the international community are developed.  Article 38 (1) of the International Court of Justice’s statute identifies three sources of international law:

  • treaties,
  • custom, and
  • general principles.

Because the system of international law is horizontal and decentralized, the creation of international laws is inevitably more complicated than the creation of laws in domestic systems.  A range of political and legal theories has influenced them.  Treaties are considered the most preferred source of international law.

The resolutions of the Security Council and the General Assembly, of the United Nations are an additional source of international law.


Inside Sources of International Law