"Luck Be a Lady" is a song written by Frank Loesser in 1950 and first performed by Robert Alda. The song was featured in the musical Guys and Dolls.
The lyrics relate the point of view of a gambler, Sky Masterson who hopes that he will win a bet, the outcome of which will decide whether or not he is able to save his relationship with the girl of his dreams.
Marlon Brando sang the song in the 1955 film version.
Jack Jones recorded it for his 1964 album, Bewitched, arranged by Shorty Rogers.
Later, it became a signature song for Frank Sinatra, first released on the album Sinatra '65, rereleased on Reprise Musical Repertory Theatre. It was released as a duet with Chrissie Hynde on Duets II (1994). The song was also recorded by Barbra Streisand for her album Back to Broadway.