This publication has its origin in the colloquium Animals and Otherness in the Middle Ages held at the Faculty of Geography and History at Complutense University in Madrid in February 2011. This publication aims to bring together scholars from a range of disciplines to consider the diverse use of animals in constructions of 'otherness'. It encompasses not only conceptualized difference, but also physical societal differences expressed in the varied treatment of real and imagined animals. The contributions also discuss the use of animals to emphasize contrast more broadly, such as the juxtaposition between good and evil, or positive and negative features.