James Jay "J. J." Barnes (born November 30, 1943, Detroit, Michigan) is an American R&B singer and songwriter. He recorded several singles, starting in 1960. His early releases including "Just One More Time" and "Please Let Me In", on the record labels Mickay and Ric-Tic, had relatively little success, but were subsequently picked up as Northern soul favorites in the UK. He was later signed to Motown Records, where he contributed as a songwriter but did not have any recordings released as a singer. Some of his Motown material has subsequently been released on the A Cellarful of Motown! compilation album series.