"I Want You Back" is a 1969 song by the Jackson 5 which became a number-one hit for the band and the Motown label in early 1970. The song, along with a B-side cover of "Who's Lovin' You" by Smokey Robinson & the Miracles, was the only single used in the Jackson 5's first album, Diana Ross Presents the Jackson 5. It went to number one on the Soul singles chart for four weeks and held the number-one position on the Billboard Hot 100 singles chart for the week ending January 31, 1970. "I Want You Back" was ranked 121st on Rolling Stone's list of The 500 Greatest Songs of All Time.

Originally considered for Gladys Knight & the Pips and later for Diana Ross, as "I Wanna Be Free", "I Want You Back" explores the theme of a lover who decides that he was too hasty in dropping his partner. An unusual aspect about "I Want You Back" was that its main lead vocal was performed by a tween, Michael Jackson.

"I Want You Back" was released on October 7, 1969 and was the first Jackson 5 single to be released by Motown and the first song written and produced by The Corporation, a team comprising Motown chief Berry Gordy, Freddie Perren, Alphonso Mizell, and Deke Richards. It also is the first of four Jackson 5 number-ones released in a row (the others being "ABC" – 1970, "The Love You Save" – 1970, and "I'll Be There" – 1970) and the first Jackson 5 song recorded in Los Angeles, California; the quintet had previously been recording Bobby Taylor-produced covers, including "Who's Lovin' You", the B-side to "I Want You Back", at Hitsville U.S.A. in Detroit, Michigan.

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