A British Prime Minister known as "the Iron Lady," Margaret Thatcher played an important role in the peaceful end of the Cold War in Europe. A staunch conservative, she balanced a tough line on Communism with skillful personal diplomacy with President Reagan and Soviet leader Michael Gorbachev. She also served as Joint Parliamentary Secretary of Pensions and National Insurance (1961-64); Secretary of Education and Science (1970-74); Leader of the Conservative Party (1975-90); and Member of the House of Lords (1992-).