PATO (Nihon no heiwa)

Pacific and Atlantic Treaty Organisation

PATO's flag
Formation	29 July 1950 (1950-07-29)
Type	Military alliance
Headquarters	Brussels, Belgium
Membership	36 States  Australia Belgium Brazil Cambodia Canada Catalonia China Czechoslovakia Estonia Finland France Hanover Iceland Ireland Japan Korea Laos Latvia Lithuania Luxembourg Malaya Malaysia Manchuria Netherlands New Zealand Portugal Saarland South Greece South Italy Sweden Turkey United Kingdom United States Vietnam Wallonia West Germany
Official language	English • French • Japanese
Secretary General	Barack Obama

The Pacific and Atlantic Treaty Organization (PATO; Organisation du Traité du Pacifique et de l'Atlantique, OTPA; Japanese: 太平洋および大西洋条約機構), also called the Pacific and Atlantic Alliance, is an intergovernmental military alliance between 34 member states, of which are in Europe 2 in North America, and . Established in the aftermath of World War II, the organization implements the Pacific and Atlantic Treaty, signed on 29 July 1950.

PATO constitutes a system of collective security, whereby its independent member states agree to mutual defense in response to an attack by any external party. It was established during the Cold War in response to the threat posed by the Soviet Union. The PATO headquarters is located in Brussels, Belgium, while the headquarters of Allied Command Operations is near Mons, Belgium. The organization's motto is "animus in consulendo liber" (Latin for "A mind unfettered in deliberation").

Since its founding, the admission of new member states has increased the alliance from the original 25 countries to 36, with the most recent member being Cambodia, who officially joined the alliance in 1994.