This article explores the way the distinction between enhancement and therapy has been used in Catholic bioethics to assess the moral character of technologies that developments in genetics and neuroscience have made possible. The purpose of drawing lines between therapy and enhancement is typically to claim that the former is always ethically justified and the latter is morally suspect, if not altogether impermissible. The author connects the enhancement versus therapy distinction to concepts of human nature that ground it and examines (...) the function of the distinction in these theological anthropologies. She argues that the distinction is insufficient for making decisions regarding use of neurotechnologies. Catholic ethicists thus need to explore alternative methods to begin the essential project of developing neuroethics. National Catholic Bioethics Quarterly 15.1 : 63–72. (shrink)