 Much contemporary disagreement about domination involves competing answers to three questions: (1) Who, or what, can dominate? (2) Is it possible to dominate merely by having power with a certain structure, or is domination an exercise or an abuse of power? (3) Exercised or unexercised, what kind of power is domination? The remainder of this entry will address each of these questions in turn, then conclude with a survey of how the idea of domination has been used in recent applied ethical theory. It will become clear as we examine competing answers to these three questions that different theorists have very different ideas of why, exactly, we need a theory of domination. There may be wide agreement that we need the idea of domination to make sense of unjust power relations, but unjust power relations are wildly varied, and theorists of domination disagree not only about which varieties most need to be understood, but about how theorizing domination helps us to understand them. 