In this collection of original essays on metaethics, the nature of morality, and the structure of moral reasoning are characterized, the limits of justification in ethics are examined, and the underlying rationale of moral philosophy is probed. Around mid-century metaethics held centre stage in discussions of moral philosophy in Anglo-American and Scandinavian philosophical environments. During the 1970s, its "foundational" position was challenged by developments within analytic philosophy itself by a renewal of systematic substantive ethics largely, but not exclusively, of a Rawlsian inspiration and by a reinvigorated interest in substantive moral problems on the part of philosophers. However, as work went on here, philosophers encountered problems concerning the methods of moral reasoning and the structure of justification of moral claims that were recognized to be metaethical. This led to a renewal of metaethics now freed from its previously narrow linguistic focus and aprioristic restrictions. The essays in this volume contribute both to this renewal and to a continued skeptical probing of the very rationale of moral philosophy.