It has been a major contention of classical natural law theory that the arguments it makes, because rooted in a robust account of human nature, are of universal applicability. A somewhat less well explored dimension is the extent to which it can admit of, and indeed support, the great variations in human cultures, life-ways and patterns of social ordering. Despite this fact, however, there is much to suggest that it is possessed of theoretical resources uniquely well adapted to maintaining a balance between unity and diversity in each of these areas. In consequence, although the disciplines of natural law and comparative law have long tended to be treated as essentially immiscible, there is much to suggest that this may not be the whole story and that an exploration of how they can be brought together holds out the promise of making real theoretical advances in each. It is in this spirit that the present volume collects together essays from a variety of scholars with interests in various aspects of classical natural law theory and comparative legal studies as a way of beginning what the editors hope will become a fruitful and, in time, much wider conversation.