The target paper claimed that notions of common ground are over- simplifi ed and under-developed, and that it seems unlikely that speech act force could be captured purely in terms of context update. The dozen responses all agree that there is more to be said about common ground, but the proff ered solutions point in many diff erent directions, while further diffi culties with reducing speech acts to context change now emerge. The exchange reveals that this is a lively area of un- resolved research.