The Afro-Blues Quintet Plus One was an American R&B-flavored soul-jazz group founded in 1963 by leader and vibes player Joe DeAguero. The group featured a unique blend of jazz with a Latin edge, characterized by a vibes/sax front line and a rhythm section that included congas and timbales alongside the standard piano, bass, and drums. The original lineup included notable musicians such as saxophonist Jack Fulks, a veteran of Chico Hamilton's band, and pianist William Henderson, who had played with Terry Gibbs' band and was versatile in playing bass, drums, flute, and vibes. The original drummer, Jim Keltner, later became one of the most renowned session drummers in pop history.

Their discography includes several albums and singles, with notable works such as "Introducing The Afro Blues Quintet Plus One" (1965), "New Directions Of The Afro Blues Quintet Plus One" (1966), and "Afro Blues Today" (1970). The group's music encompassed a variety of styles, including political and protest pieces, remakes of standards like "Green Dolphin Street," and challenging compositions such as "3/4-5/4-7-2."

The Afro-Blues Quintet Plus One was known for its innovative sound and contribution to the soul-jazz genre, leaving a lasting impact with their fusion of jazz and Latin influences.