One of the distinguishing features of most emerging technologies is that they present a broad range and diversity of ethical and social issues. Not all of these societal and ethical concerns rise to a level where they are codified into law or regulatory oversight. Traditions and values associated with communities that share a common culture or set of religious beliefs are generally not turned into laws by democratic societies unless they represent the will of most citizens. Regulatory oversight often gets postponed for any technology whose potential or perceived benefits might outweigh its risks. In arguing that regulatory agencies will slow innovation, industries have had considerable success in thwarting the enactment of new constraints on even potentially dangerous activities. In many cases though, it is the agencies’ own outdated statutory requirements and bureaucratic requirements that preclude timely regulation. Oversight is also seldom enacted for more speculative dangers based upon possibilities that may or may not come to pass. Indeed, whether the perceived risks of new technologies require anticipatory governance, in the form of precautionary measures, functions as a core debate in the formulation of science policy. That debate and other broadly shared ethical, legal and governance challenges that cut across most, if not all, of the emerging fields of research will be the focus of this volume. Companion volumes elucidate the ethical issues within individual fields of research.