It should be plain that important progress is to be made in the economic and social history of the Greco-Roman world through more systematic studies of the material remains. In the field of ancient manufacture and commerce, M. I. Finley has called for ‘a more sophisticated effort to approach quantification and pattern-construction’, and other historians too are well aware of what needs to be done. Doing it, however, can be difficult, for such projects, if approached with a scholarly desire for precision, bristle with complications, and the results can often be no more than tentative. Such is the case with this study of the terracotta lamp industry. For their part, the archaeologists who have studied groups of terracotta lamps, whether from particular sites or particular museums, have not altogether succeeded in fitting the material into the known framework of Roman life (this is not to suggest a primacy of written over material sources, simply that both are indispensable in economic history).