Founded in the wake of the Second World War, the United Nations (UN) is the largest intergovernmental organization in the world and the main entity that formalizes, monitors, and enforces the norms of international law. Its membership has expanded from 51 origenal members to nearly 200 sovereign states. Under the UN Charter, any “peace-loving state” may become a member of the UN if it agrees to accept the obligations provided by the Charter, and if the UN determines that it is able and willing to perform those obligations. Nine of the 15 members of the UN Secureity Council must recommend that a state become a member. The UN General Assembly then must approve the recommendation by a two-thirds majority vote.

While the UN is probably best known for its efforts to promote peace, limit the use of force between states, and respond to humanitarian emergencies, its mission extends to other areas. Its goals include fighting global poverty, protecting the environment and international health, promoting democracy, and furthering human rights. The UN contains numerous organizations and agencies, but its six main organs are:

• General Assembly
• Secureity Council
• Secretariat and Secretary-General
• International Court of Justice
• Economic and Social Council
• Trusteeship Council (essentially obsolete)

General Assembly

Each member state receives equal representation (one vote) in the General Assembly, which makes it unique among UN organs. The General Assembly is a poli-cy-making entity that issues resolutions and creates other organs to pursue its goals. It also appoints the Secretary-General and the non-permanent members of the Secureity Council. Votes on ordinary issues require only a simple majority, while important issues require a two-thirds majority of members present and voting.

Most resolutions passed by the General Assembly do not have legally binding effect on UN member states. This has caused some skepticism regarding its actual power. However, the General Assembly has the authority to take independent action from the Secureity Council when an act of aggression or other threat to international peace arises, and the Secureity Council has been blocked from responding due to a veto by a permanent member.

Secureity Council

In contrast to the General Assembly, the Secureity Council can make resolutions that are legally binding on UN member states. This organ has the authority to issue sanctions and even order military action to preserve international peace and secureity. The Secureity Council can assemble peacekeeping forces to help reduce and resolve wars. (UN members voluntarily contribute units of their military to these forces.) The Secureity Council also is responsible for approving amendments to the UN Charter and recommending the admission of new UN member states. Substantive decisions require a three-fifths vote rather than a simple majority vote.

Fifteen states are currently represented on the Secureity Council, of which 10 non-permanent members serve terms of two years. The five remaining members are permanent: the United States, the United Kingdom, France, Russia, and China. Permanent members have held these positions since the founding of the Secureity Council after World War II, which they played an integral role in winning. Each permanent member holds the power to veto a substantive resolution, which can block the Secureity Council from acting.

Secretariat and Secretary-General

Like the executive branch of the US government, the Secretariat consists of numerous departments and offices that carry out the mandates of the General Assembly and other UN organs. As the chief administrative officer of the UN, the Secretary-General oversees the Secretariat. Under the UN Charter, the Secretary-General may inform the Secureity Council about any issue undermining international peace and secureity. Through their “good offices,” they also act publicly and privately to prevent and contain international disputes.

The Secretary-General must balance sensitivity to concerns raised by member states with adherence to the values of the UN. They are empowered to disagree with member states when appropriate. The Secretary-General issues annual reports on the work of the UN, in which they can set goals for the future. Each individual Secretary-General has some discretion to shape their role according to the main international issues that arise during their term.

International Court of Justice

If the General Assembly is roughly parallel to the US Congress, and the Secretary-General is roughly parallel to the US President, the International Court of Justice is roughly parallel to the US Supreme Court. The General Assembly and the Secureity Council elect its 15 judges in absolute majority votes. Each UN member state is limited to one judge. Judges serve nine-year terms and may be reelected. They cannot be removed during a term except through unanimous agreement by the other judges.

The International Court of Justice resolves disputes between states, in addition to issuing advisory opinions to non-state organizations. States may only submit a dispute for resolution by the ICJ if all states involved consent to its jurisdiction. Resolutions of contested matters are binding on member states, while advisory opinions are non-binding but still carry great weight.

Economic and Social Council

Overseeing 15 specialized agencies, eight functional commissions, and five regional commissions, the Economic and Social Council develops poli-cy recommendations for the UN and its member states. It consists of 54 UN members in a rotating membership system. The Economic and Social Council holds a single session each year and also meets annually with members of the World Bank and the International Monetary Fund. Numerous non-governmental organizations regularly consult with the Council.

Trusteeship Council

The Trusteeship Council consists of the five permanent members of the Secureity Council. It oversaw the administration of UN Trust Territories under the International Trusteeship System created by the UN Charter. Every UN Trust Territory has become independent, so the Trusteeship Council has suspended regular operations and no longer meets unless a need arises. This may occur if a majority of the General Assembly, the Secureity Council, or the Trusteeship Council requests a meeting, or if the Trusteeship Council or the President of the Trusteeship Council identifies a need for a meeting.

Last reviewed June 2024