What Was Lost Was Lost" was the winner in the first novel category of the Costa Book Awards. O'Flynn received a £5,000 prize. It was short-listed for the overall Costa Book of the Year Award. The Costa Book Awards' judging panel, chaired by Joanna Trollope, praised the novel for "blending humour and pathos in a cleverly constructed and absorbing mystery." They described the novel as inventive, compelling, and poignant. "What Was Lost" was long-listed for the 2007 Man Booker Prize and the Orange Prize for Fiction. It was short-listed for the Guardian First Book Award. It won the Jelf Group First Novel Award
Bookseller/Diagram Prize for Oddest Title of the Year announced on 5 September 2008, was "Greek Rural Postmen and Their Cancellation Numbers", the 1996 winner. Bookseller/Diagram Prize for Oddest Title of the Year The "Bookseller"/Diagram Prize for Oddest Title of the Year, originally known as the Diagram Group Prize for the Oddest Title at the Frankfurt Book Fair, commonly known as the Diagram Prize for short, is a humorous literary award that is given annually to a book with an unusual title. The prize is named after the "Diagram Group", an information and graphics company based in London, and "The Bookseller", a British trade magazine for the publishing industry.