Chief executive, NHS London ▼29

Ruth Carnall is a controversial figure working in one of the NHS’s most high pressure jobs. She came into the post in 2007 after seven months as an interim, during which she asked Ara Darzi to review the capital’s £10.6bn health service. Save £5bn by 2016 through closing smaller units, setting up polyclinics and merging hospitals, he said.

But new health secretary Andrew Lansley ordered NHS London back to the drawing board, prompting the resignation of two non-executives including the chair. Now, with a highly ambitious efficiency programme and local press reporting deteriorating services, Ms Carnall faces a monumental task.

At its heart is this question: will the politicians allow the closure of dearly held local services in the name of efficiency, safety and quality, or will they play to the voters?