Anne Michaels' novel Fugitive Piece has been judged the best Orange Prize-winner to date by a panel of teenagers.
The Canadian writer, who won the award in 1997, said she was "heartened" that her work was chosen for the honour.
Michaels beat other former winners including Zadie Smith and Andrea Levy to the award, which will be presented to mark 15 years of the Orange Prize.
The honour was devised as part of the organisers' strategy to engage young people with literature.
"It means more than I can say that Fugitive Pieces has been chosen by the Orange Prize Youth Panel," said Michaels.
"Fugitive Pieces is a discussion of history, a serious enquiry into events and their consequences, what love makes us capable of, and incapable of. And it is a discussion of the deepest responsibilities of memory.
"That these questions have been embraced by the minds and hearts of young readers - the youth that is taking its place in the world - is utterly hopeful.
"I could not wish for a more meaningful honour," added the author.
The six-strong panel of A-level and university undergraduates were invited to Clarence House by the Duchess of Cornwall to discuss the shortlist.
The Youth Panel award will be presented by the Duchess as part of the 15th birthday celebrations of the Orange Prize.
First awarded in 1996, the prize recognises English language fiction written by female authors during the year in question.