This essay articulates a conception of responsibility and excuse in terms of the fair opportunity to avoid wrongdoing and explores its implications for insanity, incompetence, and psychopathy. The fair opportunity conception factors responsibility into conditions of normative competence and situational control and factors normative competence into cognitive and volitional capacities. This supports a conception of incompetence that recognizes substantial impairment of either cognitive or volitional capacities as excusing, provided the agent is not substantially responsible for her own incompetence. This conception helps frame the question whether psychopathy is excusing. The most common rationale for excusing psychopathy appeals to claims about cognitive incompetence. However, there are good philosophical and empirical reasons to be skeptical that psychopaths lack the relevant cognitive capacities. There is more to be said for a volitional rationale for excuse. The crucial question here is whether the problems psychopaths have with impulse control and conforming their behavior to the relevant moral and criminal norms are systematic enough to demonstrate genuine volitional incompetence. The available empirical evidence should leave us skeptical about the merits of this volitional rationale for excuse.