Abner Stein: Literary agent who championed American writing in the United Kingdom

For more than 30 years Abner Stein was one of London's most successful but least visible literary agents; this despite the fact that he worked with a select group of American agents and publishers on whose behalf he represented some of the most important American bestselling authors of the past 20 years. These included Dan Brown, John Grisham, Jonathan Franzen, Sue Grafton, Audrey Niffenegger, Jane Smiley, Amy Tan, David Baldacci and hundreds of others. Arguably no other literary agent had so many bestsellers, nor such a dazzling list of authors, with repeat successes every year (the Holy Grail of every publisher and literary agent).

Yet, despite this staggering success and exemplary reputation in the book trade, Stein was invisible outside it, refusing ever to speak to the press or give interviews. While some agents want to be stars, elbowing their authors aside to bask in the limelight, Stein always remained in the shadows. He believed agents had no business courting publicity, but everything to do championing their authors' interests and making publishers behave.

As one of his clients, the bestselling writer Raymond Feist, said: "Abner was old-school. Witty, knowledgeable regarding his work and the larger industry in which he practised it, Abner was the sort of person to whom a handshake was as good as a contract. He spoke truth to power, as the saying goes, dealing with authors whose egos made them as difficult as heads of state, publishers whose agendas might not necessarily be in Abner's client's best interests, and deftly navigating the shifting landscape of publishing over decades."

Abner Stein was born in Boston, Massachusetts in 1938. In 1964 he moved to London from New York when he was head-hunted to help create a new paperback publisher, Sphere, being set up by Lord Thomson, then owner of The Times. At the time Penguin and Pan were the leading imprints, although paperbacks were not yet a solid part of the ecology of the book world, as they were in the US.

Stein also founded the Poem of the Month Club, an ambitious subscription operation run from his Battersea home. Each poem was signed by the poet, and these included Fleur Adcock, Philip Larkin, Kingsley Amis, Brian Patten, Gavin Ewart, John Lehmann, DJ Enright, WH Auden, George Barker, Elizabeth Jennings, Anthony Thwaite, Stephen Spender, Roy Fuller, C Day Lewis, Stevie Smith and Robert Graves, for whose autograph Abner travelled specially to Majorca.

In 1971 Stein set up his eponymous agency. The Abner Stein Agency was, and has remained, unique because it was built on a co-agenting model – jointly representing authors in conjunction with another (almost invariably American) agency. Stein recognised very early on that literary culture, and particularly the mass market, was globalising, following trends in films and television, and that great American authors were not being properly sold into the UK. As the English, and indeed international, appetite for American writing grew, so did Stein's agency. Whether it was crime, thrillers, literary fiction or the most commercial titles, the agency, through its arrangements with New York and international agencies, had the pick of the titles.

There were two secrets to its success. First, absolutely meticulous efficiency and flawless administration in a business not recognised for world-class organisation; this is a rare and underappreciated skill. Second, an amazing nose for the potential bestseller. Stein had the enviable knack of picking out the special books that would dominate bestseller lists for weeks and make a house's fortune. These were not submitted with a perfect word-processed letter, but a short note, hand-typed by Abner himself on an obsolete Olivetti typewriter with a raised capital "S" (a troublesome letter from Mr Stein), and included Frank McCourt's Angela's Ashes, Peter Mayle's A Year in Provence and Mitch Albom's Tuesdays with Morrie.

In the late 1990s naysayers predicted the demise of co-agenting as the big publishing groups consolidated and tried to buy the biggest properties globally. But with a few exceptions this hasn't happened because it is far more important to authors to be placed with the right house (for the right money) in each market. And only a great agent on the ground can do this. Jonathan Safran Foer, a client of the agency, expressed it perfectly: "Abner Stein was, professionally, and over time personally, like a father to me. He always fiercely defended me (and 'fiercely' really is the right word here – just ask anyone who has to sit across a table from him in negotiations). He was my uncompromising champion... I always looked forward to his sly chuckle, his matzo-dry humor, his knowing smile."

Abner Stein, literary agent: born Boston, Massachusetts 6 December 1938; married 1968 Annabel Roney (marriage dissolved; two daughters); died London 12 January 2011.