Executive producer
From Tardis Wiki, the free Doctor Who reference
The title of Executive Producer was only used in the original series during Season 18. The BBC, concerned that John Nathan-Turner lacked the experience as producer for the show, assigned Barry Letts to the position for JNT's first year on the job.
It is now a consistent job in the production of the new series. Russell T Davies and Julie Gardner were the executive producers through to The End of Time, joined by Mal Young for the first series. They have been replaced by Steven Moffat, Piers Wenger and Beth Willis.