Haverstock rose to the forefront of the provincial Liberals in 1989 and was the first woman in Saskatchewan's history to lead a political party.

She brought the Liberals to realize a healthy increase in support, taking over 23 per cent of the vote in the 1991 provincial election.

[1] Under her leadership, the party grew significantly: in the 1995 provincial election, it increased its caucus in the Legislative Assembly to eleven, becoming the Official Opposition.

After leaving politics, Haverstock worked briefly as a radio host before being appointed Lieutenant Governor of Saskatchewan in 2000.

Under her direction, the province's first Summit on Tourism was held in September 2007;[2] six President's Task Teams were formed to provide guidance on key challenges and issues; a Quality Assurance Program for the sector was introduced; and the first Tourism Advocacy Day at the provincial legislature was held in November 2011.

[2] She and her husband Harley Olsen[2] (former CEO of the Office of the Provincial Capital Commission and former Deputy Minister of Municipal Affairs) have four children and nine grandchildren.