According to agent relativism, each person's moral requirements are relative to her desires or interests. That is, whether a person morally ought to ø depends on what interests or desires she has. Some philosophers charge that the main argument for agent relativism trades on an ambiguity in the term "reason," "reason for action,'' or the like. This paper shows that although the argument for agent relativism may indeed harbor an ambiguity, the ambiguity is no Achilles’ heel. To remove it is (...) not to discredit the argument, but to uncover the strongest form of it, the form that makes agent relativism tenacious. (shrink)