Julian Barnes has won the Man Booker Prize at the fourth attempt for his novel The Sense of an Ending.
He picked up the £50,000 prize at a ceremony at Guildhall in London.
Dame Stella Rimington, who chaired the judging panel, said the 150-page novel "spoke to the humankind in the 21st century".
The book is the story of a middle-aged man, Tony Webster, struggling to come to terms with his life as his past begins to unravel from the moment he receives a lawyer's letter.
Barnes has been shortlisted for the prize three times previously without winning, but Dame Stella said that "didn't figure in the debate".
She said: "It is a book about somebody who appears to be at first blush a rather boring bloke and you think 'Why are we reading about a very boring bloke?' but gradually as the book goes on you realise that this boring bloke who has presented himself in that way doesn't actually know very much about himself and gradually he's revealed to be far from that but to be somebody quite different and I think one of the things the book does is talk about the humankind.
"None of us really know who we are, we present ourselves in all sort of ways but maybe the ways we present ourselves are not how we really are and what this book does is unravel for us this person and who he really is and what's happened to him and it shows that his memory of what happened and his understanding of himself is actually quite wrong".
She said the slim volume stood up to re-reading several times and praised Barnes' style, adding: "We thought it was a beautifully written book, we thought it was a book that spoke to the humankind in the 21st century."
Jon Howells from booksellers Waterstone's said: "Julian Barnes is a worthy winner - this is not right writer, wrong book syndrome, The Sense of an Ending is a brilliant novel, one that turns in the reader's head long after finishing."
The five judges took just over 30 minutes to come to their decision and Dame Stella said it was eventually unanimous and "there was no blood on the carpet".