Despite being the subject of much recent scholarly work, torture remains an ambiguous concept. As recent legal arguments have made clear, such vagueness has important and immediate political consequences. This article makes a number of contributions towards resolving this ambiguity. First, it argues that the distinction between physical and psychological abuse is unwarranted. Second, it puts forward a logical basis for the distinction between torture and legally permissible punishments like incarceration. Third, it distinguishes between torture and related concepts like cruelty or sadism by stressing the instrumentality of torture. Ultimately, torture is defined as the systematic and deliberate infliction of severe pain or suffering on a person over whom the actor has physical control, in order to induce a behavioral response from that person.