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Customary International Law And Treaties
Whatever the map of the world may look like, at any particular time, states have generally found it important to have rules for their dealings with other states. They developed practices among themselves which formed the basis of international law - customary international law.

For example, the King of England might find it useful to have an official representative - an ambassador - to represent him in the capital of the King of France. The King of France might find it equally useful to have his own ambassador in England. The custom developed that such ambassadors would have certain privileges in their host countries, including a degree of immunity from the laws of the country. Customary international law, based on the practice of a number of states, came to cover a range of matters. It is still a very important part of international law.

Increasingly, however, modern international law is developed through treaties. Treaties are simply written agreements involving two or more states.

Many treaties are simply agreements between two states - bilateral treaties. One example is the treaty between Australia and New Zealand to foster closer economic relations between the two countries. Another example is the treaty between Australia and Papua New Guinea to define the boundary between the two countries.

Some treaties are drafted to be signed by large numbers of states - multilateral treaties. Examples are the Charter of the United Nations, and the Convention on the Law of the Sea.

Keywords: International law, treaties

Author: Nettheim, Garth