This paper explores why ethical issues associated with mental illness have been generally neglected in the literature and texts of the discipline of bioethics. I argue that the reasons for this are both philosophical and structural, involving the philosophical framework of principlism in bioethics, in particular the privileging of the principle of autonomy, and the institutional location and disciplinary boundaries of bioethics as a profession. Other contributing factors include developments outside of bioethics, in medicine and law and in the delivery (...) patterns and funding sources of mental health services, and above all the pervasive stigma that attaches to mental illness. My goal is to show both how the attention bioethics could bring would benefit this neglected area of health care, and why attending to the issues surrounding mental illness would benefit bioethics in meeting its professional obligations as the public voice on matters of ethical significance in health care. (shrink)