 If a serviceable definition of the concept of a corrupt action is to be found—and specifically, one that does not collapse into the more general notion of an immoral action—then attention needs to be focused on the moral effects that some actions have on persons and institutions. An action is corrupt only if it corrupts something or someone—so corruption is not only a moral concept, but also a causal or quasi-causal concept. That is, an action is corrupt by virtue of having a corrupting effect on a person’s moral character or on an institutional process or purpose. If an action has a corrupting effect on an institution, undermining institutional processes or purposes, then typically—but not necessarily—it has a corrupting effect also on persons qua role occupants in the affected institutions.