 Thus far this essay has focused primarily on single domain supervenience (the exceptions are the discussions of weak and intermediate global supervenience). A form of supervenience counts as single domain when and only when the A- and B-properties are possessed by the very same individuals—when the way something is in A-respects is a function of the way it is in B-respects. Both weak and strong individual supervenience are clear cases of single domain supervenience. But in some cases, what we want to say is that there cannot be an A-difference in certain things without a B-difference in certain other things—distinct things to which the former things are related in a certain way. When and if this is the case, there is multiple domain supervenience.