Earlier, she was the Chief Executive of the British Bankers' Association and, before that, a Conservative Party Member of Parliament representing the constituency of Erewash from 1992 to 1997.

She went on to set up and serve as Chief Executive of Cook & Knight Metallurgical Processors Ltd, a specialist contract heat treatment company treating precision engineering components.

[2][3] Knight became Chief Executive of APCIMS (the Association of Private Client Investment Managers and Stockbrokers) in September 1997.

[citation needed] In May 2012 it was announced that Knight had been appointed chief executive of trade body Energy UK, effective the end of July.

She has previously served as a non-executive director of Brewin Dolphin, Office of Tax Simplification, Transport for London, Financial Skills Partnership, Scottish Widows, Logica, the Port of London Authority, Lloyds TSB and South East Water.