 While these dangers cast doubt on the conviction that moral progress is inevitable or even the natural default, the model proposed by Buchanan and Powell leaves open a realistic hope for continued and deepening moral progress: it is possible for humanity to make and sustain deep moral progress, without being hamstrung by any inbuilt evolutionary constraints; but it will require ongoing cultural efforts to foster and sustain the socio-institutional circumstances that enable the better aspects of human moral nature to predominate (Buchanan, forthcoming). This is the practical message of this biocultural theory of moral progress: moral progress is possible for us without the need for biotechnological modifications of human nature; but such progress is also fragile and cannot be taken for granted (Buchanan and Powell 2018).