This article will compare and contrast two very different accounts of convention: the game-theoretical account of Lewis in Convention, and the account initially proposed by Margaret Gilbert (the present author) in chapter six of On Social Facts, and further elaborated here. Gilbert’s account is not a variant of Lewis’s. It was arrived at in part as the result of a detailed critique of Lewis’s account in relation to a central everyday concept of a social convention. An account of convention need (...) not be judged by that standard. Perhaps it reveals the nature of an important phenomenon. Looked at in that light, these very different accounts are not incompatible. Indeed, neither should be ignored if one is seeking to understand the way in which human beings arrive at some degree of social order. (shrink)