Karren began her career at LBC when she was 18 years old and swiftly moved onto Saatchi & Saatchi as junior Account Handler. She joined Sports Newspapers Ltd in 1988 and became director within a year.
Karren is now known as the first woman in football. She has been Managing Director of Birmingham City Football Club since 1993 and has turned the Clubís fortunes around. She took over Birmingham City when it was in administration, and in her first year at the helm, the Club recorded a financial trading profit. In 1996 the Club made an overall profit for the first time in modern history and in February 1997 the Club launched on the Stock market valued at the time of float at £25,000,000; she was the youngest Managing Director of a PLC in the UK. During the past years Karren has increased the average gate of the Club from 6,000 to a sell out capacity of over 30,000. In 2007 her business was valued at over £60million.