This chapter focuses on crime and punishment. Punishment involves the imposition of hardship or suffering on a supposed offender for a supposed crime, by a person or body who claims the authority to do so. Criminal punishment is problematic in at least three respects: it harms those who are punished; it also harms, indirectly, their families and friends; and it imposes significant costs on the rest of the political community. There are two strategies for the justification of punishment: instrumental and non-instrumental justifications. The instrumental strategy has been traditionally pursued by endorsing some version of consequentialism, the moral theory according to which the rightness or wrongness of a given conduct, practice, or rule depends only on its consequences. Non-instrumental justifications, on the other hand, have been traditionally defended by retributivist theories, according to which, wrongdoers deserve to suffer in proportion to the gravity of the wrong they have committed.