 As usual in practical ethics, an adequate discussion of any specific debate under this heading quickly requires orientation to the science underlying particular enhancement interventions and an appreciation of the social and political contexts in which it unfolds. At each turn in these discussions, wide vistas of background philosophical topics also appear for exploration.  Rather than providing a detailed account of this whole landscape, this entry hikes a narrow ridge between the different dimensions of the topic, pointing out the side trails but not following them into their respective thickets. Instead, it traces a path of core concerns that winds through all the current debates on the ethics of human enhancement, as guide for those interested in exploring further. To look ahead, our claim is that three sets of philosophical considerations are key to navigating this literature: first, conceptual concerns about the limits of legitimate health care, then moral worries about fairness, authenticity and human nature, and finally political questions about governance and policy.