Do non-persons have moral rights? I will suppose this question can best be answered by inquiring whether some animals and/or environmental objects have moral rights, for if any non-persons are possessors of rights, animals and/or environmental objects are the most plausible candidates. As so interpreted, this question has received an extraordinary amount of recent attention from philosophers. Arguments have been offered and defended; rebuttals have appeared in print. Yet, so far as I am aware, no one has presented a clear and accurate statement of what turns on the issue of whether non-persons have moral rights. In the absence of such a statement, philosophers are likely to be at sea in determining on which side of the controversy their initial sympathies lie. In this paper it is my central concern to help clarify what turns on the issue of whether non-persons are possessors of moral rights, rather than to argue decisively for one position or the other.