Joseph Marie Antoine Hubert Luns (August 28, 1911 – July 17, 2002) was a Dutch politician and diplomat of the defunct Catholic People's Party (KVP), now merged into the Christian Democratic Appeal (CDA). He was the longest-serving Dutch Minister of Foreign Affairs from September 2, 1952 until July 6, 1971 and later became the 5th (and also longest-serving) Secretary General of NATO for 13 years from October 1, 1971 until June 25, 1984.