There is no question that the so-called “Aristotelian unities of time, place and action” were, for several centuries, of primary importance in theatrical theory and criticism. At present, however, creative and critical reliance on these unities is slight or non-existent. Although they put up a struggle, unity of time and unity of place were eliminated some time ago. What appear to be examples may still be found, of course, but these tend to be expedients—the use of only a single setting can be vital when the economics of theatre are considered—and discussion seldom focuses on whatever unities of time or place they happen to possess. Even the concept of a single and complete action has little of the strength it once had. Shakespeare's plays are no longer deprived of their sub-plots in order to concentrate on a single action, and if the action of an “actionless” play like Waiting for Godot, for example, is “waiting,” no one would call that action complete.