The Right Honourable Hilary Jane Armstrong (born 30 November 1945) is a British Labour Party politician. She was promoted into the Cabinet of the United Kingdom as Chief Whip after the 2001 election, after spending four years as Minister for Local Government, in which time she was responsible for introducing controversial new local government structures.

Her promotion was the high point of a career which has been low key but inexorably successful; it has since taken something of a knock with controversies over select committee membership and over allegations of strong arm tactics with Labour dissenters over military action in Afghanistan.

Armstrong was educated at Monkwearmouth Comprehensive School, West Ham College of Technology and the University of Birmingham. The daughter of Ernest Armstrong MP, she inherited her father's seat (North West Durham) on his retirement in 1987 but already had her own track record as a campaigner for the North East. She remains a doughty defender of the region's interests and supports radical reform of local government to combat the stagnation of one party rule.

She was parliamentary private secretary to the late John Smith during his time as Labour leader, and played a large part in his successful fight to institute one member one vote at Labour's conference.

Her trade union links also came in useful when she helped to shore up support for the rewriting of Clause IV.