Broadcaster Robert Robinson, chairman of BBC Radio 4's Brain Of Britain and former Today presenter, is to stand down after more than three decades as quizmaster.
He will be replaced by Russell Davies, who has regularly deputised for Robert over the years.
Robert took the helm of Brain Of Britain from the programme's original host, Franklin Engelmann, in 1972. The quiz show began life as a slot in What Do You Know? in 1953, before becoming a programme in its own right.
Mark Damazer, Controller of Radio 4, said: "The brilliant Robert Robinson is retiring after more than three decades, during which he has defined the art of the quiz show host. He has presided over Brain Of Britain with sympathy for the contestants, wit and panache. It has been a joy listening to him and he will be greatly missed by the audience."
Robert said: "It feels a bit like running away from home! On the other hand, one mustn't outstay one's welcome. Faithful listeners, along with all concerned with the production of Brain Of Britain, have been so supportive over the many years. I shall be missing them and it."
On following in Robert's footsteps, Russell Davies said: "Having started listening to Brain Of Britain when Franklin Engelmann was in charge, I feel I've heard and admired Robert Robinson's entire contribution to this great tradition, and it's been a huge pleasure. His wonderful urbanity and airiness are quite inimitable. I feel myself wanting in particular to imitate his cries of regret at a wrong but attractive answer – 'Ah, Mr Bloggs, would that it were, would that it were!'
"To take over from such a well-known figure is a formidable challenge, but I'm hoping that his example will carry me through."