Is it ethical to clone a human being? Ought we to legalize euthanasia and physician-assisted suicide? Should Terri Schiavo's feeding tube have been removed? Are genetic screening and abortion of "selected" fetuses compatible with respect for disabled persons? How can we use human subjects in biomedical research without dehumanizing them? Is there a right to health care - or appropriate limits to demands for treatment? How important are human rights in a time of plague? What do we owe the starving poor in distant places? Such questions press upon us both as expert professionals and as ordinary citizens who read the paper, vote, and go to town meetings. They are also the stuff of bioethical inquiry. Bioethics is both a field of intellectual inquiry and a professional practice that examines moral questions at the intersection of biology, medicine, law, public health, policy, and ethics - all broadly construed. Unlike the traditional disciplines that contribute their respective problems and perspectives to this broadly based inquiry, bioethics is not a unitary "discipline" with its own distinctive methods and credentialing institutions. It is an interdisciplinary "field" populated by scholars, teachers, and clinical practitioners from a wide variety of traditional disciplines, such as philosophy, religious studies, law, medicine, nursing, social work, public health, the medical humanities (literature and history), and social sciences (politics, sociology, economics, anthropology).