Jóhanna Sigurðardóttir (; born 4 October 1942) is a former politician and the former Prime Minister of Iceland. She became active in the trade union movement, serving as an officer. Elected an MP from 1978 to 2013, she was appointed as Iceland's Minister of Social Affairs and Social Security, serving from 1987–1994 and 2007–2009. She has been a member of the Althing (Iceland's parliament) for Reykjavík constituencies since 1978, winning re-election on eight successive occasions. She became Iceland's first female Prime Minister and the world's first openly lesbian head of government on 1 February 2009.