When someone has committed the worst of crimes, murder, what is the appropriate punishment for that person, and what is the principled basis for that punishment? In particular, is the death penalty warranted in such cases, and if so why? Or, does capital punishment seem to be adding the state’s inhumanity to the criminal’s inhumanity? For lesser crimes as well, there are debates about the justification for criminal punishment—retribution? reparation? rehabilitation? deterrence?—where different justifications support the appropriateness of different penalties. What is the most plausible justification for criminal punishment, and what are the most appropriate punishments for different crimes?