Ancient Greek drama comprises three principal genres: tragedy, satyrdrama and comedy.1 These resemble each other in many ways, and were performed at the same festivals, but each had its own distinguishing features, which are so clear-cut that when a new papyrus fragment of a hitherto unknown dramatic text is discovered it is nearly always possible to assign it to its correct genre on the basis of language, metre and content. In what follows, therefore, it will be necessary to discuss both those features which the three genres shared (including the physical and institutional environments in which they were performed) and those which distinguished them from each other.