Donald Cameron MacDonald, CM OOnt (December 7, 1913 – March 8, 2008) was a long time Canadian politician and political party leader and had been referred to as the "Best premier Ontario never had." He represented the provincial riding of York South in the Legislative Assembly of Ontario from 1955 to 1982. From 1953 to 1970 he was the leader of the social democratic Co-operative Commonwealth Federation (Ontario Section) and its successor, the Ontario New Democratic Party.