The ends justify the means is a slogan for the belief that morally wrong actions are sometimes necessary to achieve morally right outcomes. Though such a view is implicit in many moral philosophies (especially utilitarianism), and almost all persons would be willing to commit small moral transgressions in the service of a greater good, the phrase is most often used to denote the much stronger view that any action in the service of an important enough cause is justified. This view is found in many radical political ideologies, and the atrocities committed by Jacobins, communists, capitalists, fascists, and others are often attributed to a form of moral blindness in which a powerful ultimate goal becomes an excuse to ignore ordinary moral considerations.

Few people will use the ends justify the means to describe their own views; instead, the phrase is often used to cast suspicion on the actions or motivations of others.

Some free-market libertarians, following Robert Nozick, characterize their views using the reversed slogan the means justify the ends.