Thomas Michael McMillan, is a Canadian political scientist and former politician, the country's second-longest-serving Minister of the Environment, in office from 1985 to 1988. A member of the Progressive Conservative Party of Canada, he was the Member of Parliament (MP) for Hillsborough from 1979 until 1988. McMillan is a graduate of St. Dunstan's University and Queen's University and has a doctorate in humane letters, honoris causa, from Bridgewater State University.