The International Court of Justice (ICJ; French: Cour internationale de justice; CIJ), sometimes known as the World Court, is one of the six principal organs of the United Nations (UN). It settles disputes between states in accordance with international law and gives advisory opinions on international legal issues. The ICJ is the only international court that adjudicates general disputes between countries, with its rulings and opinions serving as primary sources of international law.

The ICJ is the successor of the Permanent Court of International Justice (PCIJ), which was established in 1920 by the League of Nations. After the Second World War, both the League and the PCIJ were replaced by the United Nations and ICJ, respectively. The Statute of the ICJ, which sets forth its purpose and structure, draws heavily from that of its predecessor, whose decisions remain valid. All member states of the UN are party to the ICJ Statute and may initiate contentious cases; however, advisory proceedings may only be submitted by certain UN organs and agencies.

The ICJ consists of a panel of 15 judges elected by the UN General Assembly and Security Council for nine-year terms. No more than one judge of each nationality may be represented on court at the same time, and judges collectively must reflect the principal civilizations and legal systems of the world. Seated in the Peace Palace in The Hague, Netherlands, the ICJ is the only principal UN organ not located in New York City. Its official working languages are English and French.

Since the entry of its first case on 22 May 1947, the ICJ has entertained 181 cases through September 2021.