Julian Savulescu, professor of philosophy at Oxford University and editor of the Journal of Medical Ethics, provocatively argues that it is our duty to have designer babies. In order to achieve what he calls moral enhancement, i.e., to promote more cooperative behavior, he enthusiastically promotes two forms of human bio-engineering: genetic engineering and hormone therapy.This paper will examine the following philosophical problems with Savulescu’s project of moral enhancement: 1) the genetic determinism on which it is based is shaky scientifically and philosophically; 2) “moral enhancement” implies a moral goal, which is fundamentally in conflict with Savulescu’s view that morality is the product of mindless evolutionary processes; 3) Savulescu has no objective grounds for choosing which specific behaviors to favor; 4) if humans are so morally deficient that they need moral enhancement, how can these morally deficient individuals make wise choices that will foster moral enhancement; and 5) the method Savulsecu proposes for genetically engineering moral enhancement—embryo selection, i.e., killing embryos not considered up to snuff—is itself ethically problematic. This paper is based primarily on numerous essays authored or co-authored by Savulescu. My critique is not based so much on specific sources, but is drawn from a wide knowledge of the history and philosophy of bioethics.