Sir Anthony Charles Lynton Blair is a British politician who served as Prime Minister of the United Kingdom from 1997 to 2007 and Leader of the Labour Party from 1994 to 2007. He was Leader of the Opposition from 1994 to 1997 and held various shadow cabinet posts from 1987 to 1994. Blair was Member of Parliament (MP) for Sedgefield from 1983 to 2007, and was special envoy of the Quartet on the Middle East from 2007 to 2015. He is the second-longest-serving prime minister in post-war British history after Margaret Thatcher, the longest-serving Labour politician to have held the office, and the first and only person to date to lead the party to three consecutive general election victories.