Five arguments in favour of deliberative democracy are considered. These focus on its educative power, on its community-generating power, on the fairness of the procedure of public deliberation, on the epistemic quality of its outcomes and on the congruence of the deliberative democratic ideal ‘with whom we are’. The first four arguments are shown to be inadequate. The fifth argument, it is claimed, not only provides the most convincing defence of deliberative democracy but can also be used to decide rationally between competing interpretations of the deliberative ideal. By way of illustration, the essay concludes with a critical discussion of the rival versions proposed by Rawls and Habermas.