Started his career at Decca in 1938. He worked for Duke/Peacock for 17 years and spent time with Chess, Alladin, Apollo, United, Stax and TK before landing at Malaco in 1980.
Clark also served as the musical consultant for several movies, including The Color Purple. He wrote a column for Down Beat during the 1960s called "Swing Row Is My Beat". Clark had over 60 songs to his credit, including B.B. King's "Why I Sing The Blues". He was given a Pioneer Award by the Rhythm and Blues Foundation in 1993.