 Instead of focussing on repeated co-ordination problems, Lewis just focussed on repeated situations which collectively constitute a co-ordination problem. Lewis does not identify situations with games. A repeated situation may come in different ‘versions’, each of which is represented by a different game. For example, it may be that the costs of performing some kind of action differ on different occasions, so the formal game will be different, but the differences are small enough that it makes sense to have a common practice. And Lewis does not require that there be identity of interests. In Convention he does require that there be large overlap of interests, but this requirement does not do much work, and is abandoned in later writing. With those requirements weakened, we get the following definition of convention.