The Phantom Tollbooth is a children's fantasy adventure novel written by Norton Juster, with illustrations by Jules Feiffer, first published in 1961. The story follows a bored young boy named Milo who unexpectedly receives a magic tollbooth that transports him to the once prosperous, but now troubled, Kingdom of Wisdom. Along with a dog named Tock and the Humbug, Milo goes on a quest to the Castle in the Air seeking the kingdom's two exiled princesses, named Rhyme and Reason. As Milo learns valuable lessons, he finds a love of learning in a story full of puns and wordplay, such as exploring the literal meanings of idioms.

Norton Juster was an American academic, architect, and writer. He was best known as an author of children's books, notably for The Phantom Tollbooth and The Dot and the Line.