What sort of an organisation is the Labour Party? Its dominance of the left in Britain for over a century has produced no shortage of activists who are members, without being very enthusiastic about their membership. Various descriptions have been formulated but while all have an element of truth, none quite tell the whole story. Is Labour, as the membership cards would have it, a “democratic socialist party”? Or perhaps Tony Benn had it right when he said that Labour is “not a socialist party, but a party with socialists in it”? Is it a unique phenomenon, defined by its own special philosophy of “Labourism”?