A friendly word is best way of turning a book into a best-seller

Publishers can spend a fortune promoting their hottest literary discoveries. Bookshops can deploy all their marketing ingenuity to produce imaginative displays. But when the book-buying public comes to choose a new read, it is word of mouth that counts.

Publishers can spend a fortune promoting their hottest literary discoveries. Bookshops can deploy all their marketing ingenuity to produce imaginative displays. But when the book-buying public comes to choose a new read, it is word of mouth that counts.

A survey published today to coincide with World Book Day confirms what authors from Louis de Bernierès to Alexander McCall Smith can attest - nothing sells better than the recommendation of a friend or relative.

One in four of those polled said the last book they read was on the basis of what a colleague or family member had told them, with almost a third of under-35s citing it as the most important factor.

Only loyalty to a favoured author counted as much, with 26 per cent of readers saying their last choice of a book for pleasure was because they had read others by the same author.

In a disappointing result for the promotional teams who spend up to £100m on book advertising every year, only 6 per cent said they chose a book because they saw it advertised, with 7 per cent citing the cover design as the deciding factor.

John Bond, the managing director of HarperCollins literary division, said he was fascinated by the figures. "Publishers often stand accused of becoming ever more sophisticated and cynical in their pursuit of creating instant author brands, when ultimately it is as likely to be good old-fashioned personal recommendation that really sells."

There has been a long list in recent years of books whose first print run was low but went on to sell hundreds of thousands of copies. Top of the list is the global hit The Da Vinci Code by Dan Brown.

But McCall Smith, author of a series of books about a ladies' detective agency in Botswana, said word of mouth was not a quick way to making millions.

"I was certainly one of the beneficiaries of the word of mouth phenomenon, but it probably took a little bit of time to get going," he said. "In my case, it was about two years after publication of the first book that people were recommending them to one another and the books seemed to be taking off. What I found surprising was an awful lot of people said they had bought six copies to give to friends. People seem to want to give books to other people and share them."

The World Book Day was a "wonderful idea," he added. "It really does remind people of the great delights books offer us." Thousands of people are expected to take part in events today marking the biggest annual celebration of books and reading in the UK. It includes book tokens for every child.

In a tongue-in-cheek addition to the survey of readers' habits, people were asked to recommend a book for Tony Blair to help him win the next election. More than a third suggested How to Win Friends and Influence People by Dale Carnegie, with 18 per cent caustically recommending he study the 1997 Labour manifesto.

Gordon Brown, the Chancellor, was told to try If I Was Boss by Kes Gray to help him get where he wants to be. Other suggestions were A Conflict of Loyalty , Geoffrey Howe's memoirs detailing his clashes with Margaret Thatcher, Macbeth and Machiavelli's The Prince .

THE TOP 10 WORD-OF-MOUTH TITLES

UK sales to date

The Da Vinci Code by Dan Brown 2,211,532

The Curious Incident of the Dog in the Night-time by Mark Haddon 1,537,656

The Lovely Bones by Alice Sebold 1,301,876

Captain Corelli's Mandolin by Louis de Bernières 1,292,698

Eats, Shoots & Leaves by Lynne Truss 944,982

No 1 Ladies' Detective Agency by Alexander McCall Smith 908,362

Birdsong by Sebastian Faulks 850,790

Memoirs of a Geisha by Arthur Golden 676,492

The Alchemist by Paulo Coelho 645,447

Schott's Original Miscellany by Ben Schott 639,636

Source: Nielsen BookScan