As the President's Council on Bioethics emphasized in a recent report, rapid growth of biotechnologies creates increasingly many possibilities for enhancing human traits. This article addresses the claim that enhancement via biotechnology is inherently problematic for reasons pertaining to our identity. After clarifying the concept of enhancement, and providing a framework for understanding human identity, I examine the relationship between enhancement and identity. Then I investigate two identity-related challenges to biotechnological enhancements: (1) the charge of inauthenticity and (2) the charge (...) of violating inviolable core characteristics. My thesis is that a lucid, plausible understanding of human identity largely neutralizes these charges, liberating our thinking from some seductive yet unsound objections to enhancement via biotechnology. (shrink)