Kirsteen Sullivan was elected Labour and Co-operative MP for Bathgate and Linlithgow on 4 July 2024 with 19,774 votes (47.0 percent) and a majority of 8,323 (19.8 percent). The swing to Labour was 28.2 percent. She defeated Martyn Day of the SNP, who had held the predecessor seat of Linlithgow and East Falkirk since 2015. The constituency is new, created in the 2023 boundary review from parts of Linlithgow and East Falkirk and Livingston. Sullivan was its first MP.

Born Kirsteen Ann Sullivan in Glasgow in July 1975, she was educated at St Ninian's High School before studying at Glasgow University, where she took an MA, and the University of Strathclyde Business School, where she completed an MSc. She worked as a business analyst, first for Prudential, then for Scottish Widows, before becoming director of a programme management consultancy. She moved from Glasgow to Bathgate around 2008.

Her political career began in local government. She was elected as a Labour councillor for the Whitburn and Blackburn ward on West Lothian Council in 2017 and served as Depute Leader of the council from 2017 to 2024, seven years in one of the most senior positions in West Lothian local government. She resigned her council seat on 26 September 2024 following her election to Parliament. The Depute Leader role is not a ceremonial position. West Lothian Council serves approximately 183,000 residents and manages budgets under sustained real-terms pressure from the Scottish Government. Sullivan was responsible for council operations during a period when, as she put it, "council budgets have seen real term cuts from the SNP government over a number of years and front line services are struggling."

Her campaign was not without difficulty. There was a row within the local party over how much of its resources should be spent on the Bathgate and Linlithgow campaign and how much kept in reserve. Some activists were said to have left Sullivan's campaign team to work in the neighbouring Livingston constituency instead. Sullivan did not comment publicly. Keir Starmer and Scottish Labour leader Anas Sarwar visited the constituency during the campaign, touring a window factory in Whitburn.

Since entering Parliament she has sat on the Scottish Affairs Committee (since October 2024) and the Administration Committee (since April 2025), and joined the All Party Parliamentary Groups on Sexual Exploitation and on Menopause. Her stated priorities are supporting local businesses, improving public services and driving investment in the constituency. She has focused on constituency representation rather than pursuing a national media profile.

Sullivan's strengths include genuine executive experience in local government (seven years as Depute Leader), a substantial 19.8 percent majority in a new constituency, a professional background in business analysis and programme management that is unusual among Labour MPs, and deep roots in the area she represents. Her weaknesses are those common to the 2024 intake: no ministerial office, no committee chairmanship, limited national visibility, and a parliamentary record still being established.

At 50, she is older than much of the 2024 intake and brings more professional and local government experience than most. The Depute Leader role means she has already managed budgets, made difficult decisions about service provision, and navigated the politics of coalition and minority administration on a council. Whether she uses that experience to build a Westminster career beyond the backbenches or concentrates on representing Bathgate and Linlithgow is the open question. The foundation is stronger than most first term MPs start with.