"Who Are You" is the title track on the Who's 1978 album, Who Are You, the last album released by the group before Keith Moon's death in September 1978. It was written by Pete Townshend and released as a double-A-sided single with the John Entwistle composition "Had Enough", also featured on the album. The song was one of the band's biggest hits in North America, peaking at number 7 in Canada and at number 14 in the United States, and has become one of the band's signature tunes at their live shows. The piano on the track is played by Rod Argent.

Peter Dennis Blandford Townshend is an English musician. He is the co-founder, guitarist, second lead vocalist and principal songwriter of the Who, one of the most influential rock bands of the 1960s and 1970s. His aggressive playing style and poetic songwriting techniques, with the Who and in other projects, have earned him critical acclaim.