The principal aim of this book is to develop and defend an analysis of the concept of moral obligation. The analysis is neutral regarding competing substantive theories of obligation, whether consequentialist or deontological in character. What it seeks to do is generate solutions to a range of philosophical problems concerning obligation and its application. Amongst these problems are deontic paradoxes, the supersession of obligation, conditional obligation, prima facie obligation, actualism and possibilism, dilemmas, supererogation, and cooperation. By virtue of its normative neutrality, the analysis provides a theoretical framework within which competing theories of obligation can be developed and assessed. This study is a major contribution to metaethics that will be of particular interest to all philosophers concerned with normative ethical theory.