Spain in the Atlantic Alliance and in the United Nations
Background
NATO's own membership page records that Spain joined the Alliance on 30 May 1982, the only country to accede in that enlargement. NATO's list of member countries, which names Spain among them, runs to 32 states, from the twelve founding members of 1949 to Sweden. The United Nations list of member states gives Spain's date of admission as 14-12-1955. Spain is therefore not an original member of the United Nations but joined a decade after the Organization was founded. Its Minister of Defence, Margarita Robles, deals directly with NATO's strategic commands, and Spanish contingents serve in Alliance operations.
In plain words
NATO North Atlantic Treaty Organization — A military alliance of European and North American states with its political headquarters in Brussels.