After lecturing in political studies at Auckland University, she was elected to parliament in 1981 as a Labour MP. She served in the cabinet from 1987–1990, was leader of the opposition from 1993–1999, and was three times (1999, 2002, and 2005) Prime Minister at the head of various Labour-led coalitions. Her government presided over a period of economic growth while enacting social and welfare reforms. From 2009 she was Administrator of the United Nations Development Programme.