Belgium, Netherlands and Luxembourg constitute Benelux.
Luxembourg
Luxembourg, officially the Grand Duchy of Luxembourg, is a landlocked country in Western Europe. It is bordered by Belgium to the west and north, Germany to the east, and France on the south. Its capital and most populous city, Luxembourg City, is one of the four institutional seats of the European Union and hosts several EU institutions, notably the Court of Justice of the European Union, the highest judicial authority in the EU.
Benelux
The Benelux Union or Benelux is a politico-economic union, alliance and formal international intergovernmental cooperation of three neighbouring states in Western Europe: Belgium, the Netherlands, and Luxembourg. The name is a portmanteau formed from joining the first few letters of each country's name and was first used to name the customs agreement that initiated the union. It is now used more generally to refer to the geographic, economic, and cultural grouping of the three countries.