 Our discussion of the completeness question has so far yielded negative results: supervenience physicalism is too weak, type physicalism is too strong, and token physicalism is both too weak and too strong. What seems to be required is an approach that, like the modal formulations we started with, entails the supervenience of everything on the physical, but unlike them avoids the sufficiency problem. One prominent idea along these lines appeals to a relation between properties distinct from both identity and supervenience, usually called realization. As in the case of identity physicalism, there are two different versions of realization physicalism as we may call it; we will consider them in turn.