Psychopathy presents a difficult challenge to moral and criminal responsibility theorists. Persons with the disorder have an impaired capacity for empathy and other moral emotions, and fail to feel the force of moral considerations. They have some rational impairments, but they reason adequately to manipulate, con, and exploit their victims, and otherwise to engage successfully in antisocial behavior. Is it appropriate to hold them morally responsible for their wrongdoing? Should the law hold psychopaths criminally responsible? This essay discusses philosophical debates involved in addressing these questions.