After training as an economist and working as a macroeconomic forecaster at the Economist Intelligence Unit, she was elected Member of Parliament (MP) for Burnley at the 2005 general election, succeeding Peter Pike. Seen as a high flier, she went on to serve as a minister in Gordon Brown's government from 2007 to 2009, mainly at the Treasury, but also at the Department for Work and Pensions, having previously been a Special Advisor at the Department for Trade and Industry. At the time she was the second-youngest government minister, and the youngest woman.