The later twelfth and thirteenth centuries were a pivotal period for the development of European government and governance. During this period a mentality took hold which trusted to procedures of accountability as a means of controlling officers conduct. The mentality was not inherently new, but it became qualitatively more complex and quantitatively more widespread in this period, across European countries, and across different sorts of officer. The officersexposed to these methods were not just state ones, but also seignorial, ecclasistical, and university-college officers, as well as urban-communal ones. This comparative study surveys these officers and the practices used to regulate them in England. It places them not only within a British context butalso a wide European one and explores how administration, law, politics, and norms tried to control the insolence of office.The devices for institutionalising accountability analyzed here reflected an extraordinarily creative response in England - and beyond - to the problem of complex government: inquests, audits, accounts, scrutiny panels, sindication. Many of them have shaped the way in which we think about accountability today. Some remain with us. So too do their practical problems. How can one delegate control effectively? How does accountability relate to responsibility? What relationship does accountabilityhave with justice? This study offers answers for these questions in the Middle Ages, and is the first of its kind dedicated to an examination of this important topic in this period.