Conservative talk of a 'big society' is one more mutation of the unstable family of pluralism. It is a large family, with both benign and progressive left wing members and rogue right wing black sheep. The progressive contribution has been substantial, but pluralism is not a homogeneous ideology or set of policies, and the single word conceals stresses and irreconcilable oppositions in theory and practice. An examination of this variety gives clues to the latest contributions, and to some of the more regressive uses to which pluralism can be put. The left needs both to insist on its own major contribution to progressive pluralism, and to beware of wolves in pluralist clothing. © The Author 2011. The Political Quarterly © The Political Quarterly Publishing Co. Ltd. 2011.