International relations is the study of interactions among sovereign nation/states. In a broader sense, it concerns all activities between states—such as war, diplomacy, trade, and foreign policy—and relations with and among other international actors, such as intergovernmental organisations (IGOs), international non-governmental organisations (INGOs), international legal bodies, and multinational corporations (MNCs).
International law refers to the body of laws governing interactions between nations. International law can be divided into two distinct categories:
Public International law focuses on relationships between nations and citizens of different nations as governed by various inter-governmental organizations, such as the United Nations and NATO, and other sources of law such as treaties and custom. For example, a dispute over a waterway between two nations would be governed by Public International law.
Private International law is synonymous with the concept of "conflict of laws"; that is, it refers to legal disputes, typically involving private citizens, in which jurisdictional issues are the primary area of inquiry. For example, a contract dispute between citizens of two different countries would likely be governed by Private International law.
Approaching a research problem in International Law and Relations shares many similarities to approaching an American legal research problem though the materials used may differ.