This book introduces the history and nature of international law and examines its sources-treaties, customary international law, general principles, jus cogens, and equity-and the different forums in which it is interpreted and applied. It also covers important fields of international law: individual and human rights; recognition and self-determination; war and peace; and more. It examines U.S. cases on the application of international law in the U.S. legal system, the proliferation of international courts and tribunals, the responsibility of states and international organizations, and the International Criminal Court.