A working language (also procedural language) is a language that is given a unique legal status in a supranational company, society, state or other body or organization as its primary means of communication. It is primarily the language of the daily correspondence and conversation, since the organization usually has members with various differing language backgrounds.
Most international organizations have working languages for their bodies. For a given organization, a working language may or may not also be an official language.
Originally, English and French were the working languages at the UN. Later, Arabic, Chinese, Russian, and Spanish were added as working languages in the General Assembly and in the Economic and Social Council. Currently, Arabic, Chinese, English, French, Russian, and Spanish are the working languages of the Security Council.
The International Criminal Court has two working languages: English and French. The Council of Europe, the OECD, and NATO also have English and French as their two working languages.
The World Organization of the Scout Movement (WOSM) has English and French as official languages, with Arabic, Russian, and Spanish as additional working languages.
The Organization of Ibero-American States (OEI), Ibero-American General Secretariat (SEGIB), Mercosur, and the Latin American Integration Association have two working languages: Portuguese and Spanish.
The World Trade Organization, the International Federation of Journalists, the International Telecommunication Union, the International Maritime Organization, the International Labour Organization, NAFTA, the International Union for Conservation of Nature, and the Free Trade Area of the Americas all have three working languages: English, French, and Spanish.