The North Atlantic Treaty Organization (NATO) is an intergovernmental military alliance founded in 1949. It has 32 member states in Europe and North America.

NATO’s collective-defence principle is set out in Article 5 of the North Atlantic Treaty: an armed attack against one member is considered an attack against all. The alliance also serves as a system of deterrence.

In the news context, suspected drone incursions and sightings over sensitive sites have affected NATO countries. NATO referred requests for figures on drone incidents to national authorities, which track the information through different mechanisms.