Clarence Williams III (August 21, 1939 – June 4, 2021) was an American actor. Williams was the son of a professional musician, Clarence "Clay" Williams Jr., and grandson of jazz and blues composer/pianist Clarence Williams and his singer-actress wife, Eva Taylor. Raised by his paternal grandmother, he became interested in acting after accidentally walking onto a stage at a theater below a Harlem YMCA.

Williams began pursuing an acting career after spending two years as a U.S. Army paratrooper in C Company, 506th Infantry, of the 101st Airborne Division. He first appeared on Broadway in The Long Dream (1960). Continuing his work on stage, he appeared in Walk in Darkness (1963), Sarah and the Sax (1964), Doubletalk (1964), and King John. His breakout theatrical role was in William Hanley's Slow Dance on the Killing Ground, for which he received a Tony Award nomination. The New York Times drama critic Howard Taubman wrote of his performance, "Mr. Williams glides like a dancer, giving his long, fraudulently airy speeches the inner rhythms of fear and showing the nakedness of terror when he ceases to pretend." He also served as artist-in-residence at Brandeis University in 1966.