 In 1976, Imbert left the Met and became Assistant Chief Constable, and later Deputy Chief Constable of Surrey Constabulary.In 1979, he became Chief Constable of Thames Valley Police, the youngest Chief Constable in the country at that time.During his time at Thames Valley, Imbert allowed the BBC to make "Police", a 1982 fly-on-the-wall documentary series about the police at work.