The social and medical ethos within which bioethics emerged in the late 1960s and early 1970s was constituted in part by religious questions and religious thinkers. However, this identifiably religious influence on bioethics subsequently seemed to decline. How has this diminished impact come about, and what significance, if any, does it hold for the ways we now do bioethics? What difference, finally, do religious perspectives make for bioethics? These were the overarching questions that led the Hastings Center to initiate a research project on the relation of Religion and Bioethics, culminating in this special supplement to the Hastings Center Report.