It is often regarded as a companion piece to "Thanks for the Memory", written for the February 1938 film The Big Broadcast of 1938 by Leo Robin and Ralph Rainger and also performed by Bob Hope and Shirley Ross.
The song tells of a young couple in love, who, despite being sleepy, do not wish to say goodnight, which implies a kind of parting. To solve the problem, the two get married, but nothing changes. They are still awake at dawn, because they love each other so much.
As well as being recorded by Carmichael himself, the song has been performed and recorded by a number of artists including Al Bowlly, Bing Crosby, Sammy Davis, Jr., Art Garfunkel, Vince Jones, Julie London, Dean Martin, Carmen McRae, Silje Nergaard, Jack Pleis, Carly Simon, Peter Skellern, Fats Waller, Hank Jones, and a duet with Alice Babs and Ulrik Neumann and Carsie Blanton, and another duet by Seth MacFarlane and Norah Jones. It was also performed on the short-lived variety show with Twiggy, the former model, and Jeremy Brett, renowned for his portrayal of Sherlock Holmes.
The song was performed by Dorothy Lamour on the October 30, 1938 broadcast of the Chase and Sanborn Hour radio program.
It was recorded by Philip and Vanessa in 1974 and was a minor hit.