abstract Normative argument is supposed to guide ways in which we might change the world, rather than to fit the world as it is. This poses certain difficulties for the notion of applied ethics. Taken literally the phrase ‘applied ethics’ suggests that principles or standards with substantial philosophical justification, in particular ethical and political principles with such justification, are applied to particular cases and guide action. However, the ‘cases’ which applied ethics discusses are themselves indeterminate, and the relation of principles to these ‘cases’ differs from the relation of principles to cases in naturalistic, truth-oriented inquiry. Writing in ‘applied ethics’, I shall argue, does not need elaborate case histories or scenarios, since the testing points for normative principles are other normative principles rather than particular cases. Normative principles and contexts to which they are applicable are indeed needed for any reasoning that is practical, but they are not sufficient. Practical ethics needs principles that can not merely be applied in certain cases or situations, but also enacted in certain ways, and requires an account of practical judgement and of the public policies that support that judgement.