World peace-keeping body headquartered in New York City.
- Princess Ingrid of Scandinavia visits Washington five years after her father spoke at the United Nations [Episode #2: "Diplomat's Daughter"].
- Trinka Markoff, daughter of the late Boravian prime minister, passes through Washington on her way to New York to address the U.N. [Episode #65: "Maxwell Smart, Private Eye".]
- The runaway robot named Fred takes refuge in the United Nations Building where he registers himself as the newly-emerged country of "Fredonia." On his trail, Maxwell Smart and inventor Blossom Rose encounter Noel, a FLAG agent posing as a guide there. Simultaneously, FLAG agent Captain 49 plans to destroy the U.N. Building with a torpedo fired from a submarine hidden in the East River [Novel #1: "Get Smart!"].
- After reports of Nude Bomb attacks at various locations around the world, Max attends a meeting of the U.N. Security Council to reassure the delegates that the Nude Bomb does not exist. Unfortunately, his message is undercut when such an attack occurs at that very meeting [American Ambassador portrayed by Walter Brooke, Movie: "The Nude Bomb"].
See United Nations at Wikipedia.