There have been numerous people who have served in both the Senate and the House of Representatives, most notably John Gorton who was appointed Prime Minister, while still a member of the Australian Senate, following the disappearance of Harold Holt in December 1967. In accordance with section 43 of the Constitution, Gorton resigned his seat in the Senate to contest Holt's now vacant and ultra-safe seat of Higgins at the subsequent by-election. Gorton maintained his office as Prime Minister under section 64 of the Constitution.