NATO

Coordinates: 50°52′34.16″N, 4°25′19.24″E

The North Atlantic Treaty Organisation (NATO; French: Organisation du Traité de l'Atlantique Nord ("OTAN"); also called the North Atlantic Alliance, the Atlantic Alliance, or the Western Alliance) is a military alliance, established by the signing of the North Atlantic Treaty on April 4, 1949. With headquarters in Brussels, Belgium, the organisation established a system of collective defence whereby its member states agree to mutual defense in response to an attack by any external party.