Ronald William Gordon Mackay (3 September 1902 – 15 January 1960), known as Kim Mackay, was an Australian-born British Labour Party (and briefly Common Wealth Party) politician known for his European federalist views. Born in Bathurst, New South Wales, Mackay studied law and education at the University of Sydney. In 1926, he became a part-time history lecturer at St. Paul's College, and in 1932 he was a co-founder of the Australian Institute of Political Science, which argued for reform of the Australian Constitution.