This is a short preface for quite a lengthy book, but it is a means of paying tribute to those principally involved in the development, shaping and production of The Cambridge history of the Byzantine empire (or CHBE). Like the empire itself, the process of formation has been protracted, without a clear-cut starting-point, and such sense of direction as has been attained owes more to collaborative effort than it does to untrammelled autocracy. Given the sizable number of persons contributing in one way or another, the preface’s brevity entails a mere sketch of those without whose help and advice CHBE would have been a far more onerous and lengthy task. It was Bill Davies who originally encouraged me to take on remodelling materials already available, and several anonymous readers helped structure the volume. Michael Sharp took over from Bill at Cambridge University Press and he has been an extremely patient and supportive editor, ably assisted at various times by Liz Davey, Sinead Moloney, Liz Noden and Annette Youngman. Particular thanks should go to the following key players: Bernard Dod, our indefatigable and eagle-eyed copy-editor, whose attention to detail and wise counsel averted many a mishap; toBarbaraHird, our expert indexer, whose care and clarity have created a valuable additional pathway to Byzantium; to Patricia Jeskins, our assiduous proofreader; and toDavid Cox, our cartographer, whose splendid maps are closely integrated with the text of our chapters. For bibliographic help I have to thank the following colleagues, who have supplied references and answered tiresome queries with speed and good grace: Jean-Claude Cheynet, Florin Curta, Peter Frankopan, Judith Gilliland, Michael Gr¨unbart, Paul Herrup, James Howard-Johnston, Elizabeth Jeffreys, Lester Little, Margaret Mullett, Angel Nikolov, Paolo Odorico, Maureen Perrie, G¨unter Prinzing, Charlotte Rouech´e, Maciej Salamon, Alexios Savvides, Teresa Shawcross, John Smedley, Tsvetelin Stepanov, Alice-Mary Talbot, George Tcheishvili, Ida Toth, Vladimir Vavˇr´ınek and Mark Whittow. I should also like to thank the staff at the Bodleian, Taylorian Slavonic, Sackler, Oriental Institute and the other Oxford libraries, as well as the staff of the University Library in Cambridge. Colleagues who clarified various points along the thousand-year trek, or who freely provided access to unpublished materials of value for this work include Jane Baun, Jeffrey Featherstone, Paul Fouracre, JohnHaldon, RosemaryMorris, Pananos Sophoulis andMonica White. Particular thanks are due to Catherine Holmes, Mike Maas and Andrew Roach, who read the introduction and some of the chapters that follow, and who warned of culs-de-sac and quicksands to be charted or – hopefully – avoided. On the technical side, help with translation and transliteration was given by Lawrence Conrad, Jeffrey Featherstone, Tim Greenwood, Mona Hamami and Marina Kuji´c. Jenny Perry saved me on several occasions when Macs failed to talk to PCs, and vice versa, while Nigel James of the Bodleian initiated me into the mysteries of digital map-making. Locating and sourcing illustrations was made easier through the assistance of Nancy Alderson, Michel Balard, Theodore van Lint, Cyril Mango, Nicholas Mayhew, Dorothy McCarthy, Denys Pringle, Michael Stone and Robert Thomson. Particular thanks go to our neighbours, Vanessa and Peter Winchester, to whom I am indebted for several pictures of Constantinople. These thanks should be accompanied by apologies for a certain lack of sociability in recent years – and extended to all remaining friends. It is a commonplace to thank one’s immediate family for their help and endurance in these endeavours.However, I must single out my wife,Nicola, who took on the role of editorial assistant on the project without, I think, appreciating the sheer scale of activity involved. As I have often pointed out to her, this could be seen as due penance for failing to attend my lectures on Byzantium and its neighbours all those years ago in Cambridge! Without Nicola, the volume would probably not have been published this decade, and I am profoundly grateful for her patience, counsel and support. However, those most indispensable are the volume’s contributors. The chapters whose first incarnation was in The Cambridge ancient history or The new Cambridge medieval history have been joined by important new contributions expanding and elaborating on relevant themes. But it goes without saying that, notwithstanding all the help and advice received along the way, I take responsibility for such mistakes or errors as may have crept into the finished work.