Comedy writer David Nobbs, best known for creating the television character Reginald Perrin, has died, the British Humanist Association (BHA) said.
The 80-year-old from North Yorkshire, also contributed to The Two Ronnies, Ken Dodd, Tommy Cooper and Frankie Howerd as well as writing 20 novels.
Nobbs wrote the Reginald Perrin novels which were turned into a much-loved sitcom that originally ran between 1976 and 1979.
They starred Leonard Rossiter as a man constantly on the verge of a mid-life crisis but with a vivid imagination.
Tributes poured in from the world of comedy for Nobbs.
Stephen Fry wrote: "Oh no! David Nobbs has died. I liked him very very much. Such a brilliant comic writer and such a kind, wise man."
John Cleese described the Perrin shows as his "masterwork".
He posted on Twitter: "Very sad today to hear of the death of David Nobbs. First worked with him on the Frost Report in 1966... a lovely kind, gentle man with a delicious sense of humour.
"He wrote many top-class shows and books."
The Office creator Ricky Gervais, borrowing a catchphrase from Perrin's tyrannical boss CJ, said: "I didn't get where I am today by not knowing what a genius David Nobbs was. RIP."
Little Britain star Matt Lucas wrote: "Reggie Perrin and A Bit Of A Do were masterpieces. David Nobbs leaves the world a richer place."