This book examines the role of written agreements in eleventh- and twelfth-century Catalonia, and how they determined the social and political order. In addition to offering insights into subjects as diverse as the power of counts and bishops and the organization of rural societies, it addresses several current debates in medieval studies: the question of feudalism, the "transformation of the year 1000, " medieval literacy, and the nature of Mediterranean societies. It is thus a local study that has wide implications for the history of medieval Europe.