Bill Hayden, Australian politician, 21st Governor General of Australia
William George Hayden (born 23 January 1933) is an Australian politician who served as the 21st Governor-General of Australia from 1989 to 1996. He was Leader of the Labor Party and Leader of the Opposition from 1977 to 1983, and served as Minister for Foreign Affairs and Trade from 1983 to 1988 under Bob Hawke and as Treasurer of Australia in 1975 under Gough Whitlam.

Hayden was born in Brisbane, Queensland. He attended Brisbane State High School and then joined the Queensland Police, working as a police officer for eight years while studying economics part-time at the University of Queensland. Hayden was elected to the House of Representatives at the 1961 federal election, aged 28 – along with Manfred Cross and Doug McClelland, Hayden is the earliest elected Labor MP still alive. When Gough Whitlam led the Labor Party to victory in 1972, he was made Minister for Social Security. He replaced Jim Cairns as Treasurer in 1975, but served for only five months before the government was dismissed.

In early 1977, Hayden challenged Whitlam for the party leadership and was defeated by just two votes. He defeated Lionel Bowen to succeed Whitlam as Leader of the Opposition at the end of the year, following Labor's defeat at the 1977 election. Hayden led the party to the 1980 election, recording a substantial swing but falling well short of victory. He was replaced by Bob Hawke just a few weeks before the 1983 election, after months of speculation. Hayden served as Minister for Foreign Affairs and Trade from 1983 to 1988, then left parliament to assume the governor-generalship. He held that position for seven years, with only Lord Gowrie having served for longer.