Jana Bennett has been appointed director of television at the BBC, one of the most powerful jobs in British television.

Bennett joins from Discovery Communications in the USA, where she is currently executive vice-president and general manager. She replaces Mark Thompson, who quit the BBC last year to join rival broadcaster Channel 4 as chief executive.

In her new job, Bennett will oversee all programme commissioning and acquisitions - including film acquisitions - for BBC1, BBC2, digital channels BBC Choice and BBC4 and international channels BBC America, BBC Canada and BBC Prime.

Bennett is no stranger to the BBC. She began her career there as a news trainee in 1979, rising to director of programmes in the former Production division. At the BBC, she was highly regarded and noted for her successful track record in science programming, with credits including Walking With Dinosaurs and The Human Body. She left to join discovery in August 1999.

BBC director general Greg Dyke commented: "Jana's experience and success running a channel in the American multi-channel market gives her an invaluable perspective."