The Orange Book, published in 2004, is the unofficial manifesto of the Liberal Democrats' right wing. Edward Stourton examines its influence on both the party and the coalition.

The Orange Book, published in 2004, is a collection of political essays by leading Liberal Democrats. Although the writers come from a range of viewpoints, the book has been seen as an attempt by party right wingers to reclaim the party's economic liberal origins in the nineteenth century and give it a new modern emphasis. But for some leading Liberal Democrats these ideas are now closer to tenets of Conservative thought. So will the Orange Bookers bind the coalition ever closer together or lead to fractures and even splits in Liberal Democrat ranks?

Edward Stourton talks to one of the leading Orange Book Liberal Democrats, David Laws MP, about the philosophy behind the book and why they were so keen to publish it. He discusses the consequences for the party of the gap which has now emerged between public perceptions of where the party stands on major issues and where its leadership's inclinations lie. And he discusses what the longer-term implications of the Orange Bookers' relationship with David Cameron's Conservatives will be.

Among those he talks to are Baroness Williams of Crosby; the former Conservative Shadow Home Secretary, The Rt. Hon. David Davis, MP; the historian and newly-elected Labour MP, Tristram Hunt; the expert on political leadership, Professor Peter Clarke; and the former Liberal Democrat policy director and Orange Book sceptic, Richard Grayson.