Abstract: Suppose that you have a choice of two actions, A and B, and suppose that action A has better prospects for everyone than action B. Then many would conclude that A is “ex ante pareto superior” to B, and so that you should do A rather than B. I have argued that a person’s prospects can depend on how they are designated, and so for an action to count as ex ante pareto superior we must consider the prospects for every individual under every relevant designator. But what is the domain of relevant designators? If we include all designators, then we get strongly counter-intuitive results. If we impose an arbitrary restriction on the domain, then we get an arbitrary restriction on the scope of the principle. The aim of the paper is to pinpoint the category of designators that gives us the right domain.