"Girlfriend" is a song written by Paul McCartney. McCartney thought of the song as one that Michael Jackson might like to record, and mentioned this to Jackson at a party in Hollywood. Jackson had stated in interviews with the music press in the 1970s that he was a fan of The Beatles and the chance to record a McCartney original helped to inspire his next project. However, McCartney ended up recording it himself with his band Wings, and it was issued in 1978 on the album London Town. Subsequently, it was suggested by Quincy Jones as a possible track for Jackson to record for his 1979 album Off the Wall. Jones was unaware that the song had been written for Jackson in the first place. Jackson's recording omitted the middle eight heard in McCartney's version. It was issued exclusively in the UK in 1980, as the fifth and final single from the Off the Wall album. This proved to be another hit single for Jackson and one of his first recordings of a Paul McCartney song.

McCartney and Jackson subsequently worked together on "The Girl Is Mine" from Thriller, as well as "Say Say Say", and "The Man" from Pipes of Peace. In 1985, Jackson acquired the ATV Music Publishing catalog (which held the rights to nearly every Beatles song) uncontested by McCartney. According to McCartney, they "drifted apart" after he talked to Jackson about getting a "raise" and Jackson did not act on it.

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