He was also a founding member of the American Composers Alliance (of which Aaron Copland was the first president); involved extensively with the Curtis Institute of Music; a board member of the League of Composers; Director of the Philadelphia Music Center and active in the US civil rights movement.
He was also one of the original members of the American Composers Alliance (Aaron Copland served as the first president); he was deeply involved with the Curtis Institute of Music; a board member of the League of Composers; Director of the Philadelphia Music Center and active in US civil rights issues.