Harold Arlen,/Johnny Mercer.
The song was published in 1942 and has become an often-recorded standard with versions that include the original single release by Glenn Miller, the singers Margaret Whiting, Frank Sinatra, Sammy Davis, Jr., Mercer himself, and others. Mercer wrote the lyrics with Judy Garland in mind, who was, on occasion, an intimate partner. Garland recorded the song for Decca Records
in 1942. Mercer recalled wanting to write a song about magic, and while
composing, asking Arlen to write more music so the song could go on
longer, but that they still wrote the whole song in about three hours