Book excerpt: The invisible force of authority bound the diverse groups in the Byzantine state and maintained its existence across many centuries. The present volume brings together an international cast of contributors to explore the many aspects and construction of authority within the state, the church and the family. They examine the authority of knowledge and text, the depiction of authority, and lastly, the legacy of three great scholars of Byzantine studies. Five of the sections are followed by responses from a specialist in the western middle ages bringing a wider European perspective to the subject.