From 1942 to the present day – Desert Island Discs is one of BBC Radio’s longest-running programmes.

Late one evening in 1941, freelance broadcaster Roy Plomley was at his home in his pyjamas, when an idea came to him. He sat down and wrote immediately to the BBC. That letter reached the in-tray of the BBC’s Head of Popular Record Programmes, Leslie Perowne. The pitch was successful and a broadcasting institution was born.

http://www.bbc.co.uk/radio4/features/desert-island-discs