‘Byzance au tournant de son destin’ was how Paul Lemerle characterised the empire inherited by the Komnenoi. In the essay which he published under this title, Lemerle challenged the notion, fostered by Byzantine historians of the period and adopted by modern Byzantinists, that the eleventh century was a period of decadence in Byzantine society, when the achievements of the ‘golden age’ of the Macedonian dynasty, crowned by the triumphs of Basil II, were undone by the irresponsible policies of Basil's successors, most notoriously Constantine IX Monomachos. Although the cultural activity of the eleventh century had received due appreciation, and the idea that the period was one of economic decline had not gone unchallenged, Lemerle was the first to point out that the discredited policies of the civilian emperors had their merits, and could be seen as responses to a process of economic, social and cultural expansion. With this recognition, Lemerle made it possible for Byzantinists to regard the very failures and crises of the period as symptoms of constructive changes at work in Byzantine civilisation. Although he drew no comparison with the West, he clearly postulated a model of development comparable to that which western medievalists had always taken for granted: one of progress towards a more complex, mobile, professionally articulate and politically open civil society. In particular, the political role of the guilds and the Church in the mid eleventh century, and the flourishing study of law were developments which, in a western context, would inevitably be regarded as advanced.