The Benelux is a customs union in Europe comprising three neighbouring countries, Belgium, the Netherlands, and Luxembourg. These countries are located in northwestern Europe between France and Germany. The Union's name is formed from the beginning of each country's name; it was possibly created for the Benelux Customs Union. However, according to The Economist it was coined somewhat earlier—in August 1946, by that newspaper's correspondent in Belgium. It is now used in a more generic way to refer to the cultural, economic, and geographic grouping.

In 1951, these countries joined West Germany, France, and Italy to form the European Coal and Steel Community, the earliest version of the modern European Union.

The main institutions of the Union are the Committee of Ministers, the Parliament, the Council of the Union, the Court of Justice, the Secretariat-General, the Organization for Intellectual Property.

The Benelux Secretary-General is located in Brussels. It is the central administrative pillar of the Benelux Economic Union. It handles the secretariat of the Committee of Ministers, the Council of Economic Union and the various committees and working parties. Moreover, it ensures the registry of the Benelux Court of Justice.