An important human trait is our inclination to develop complex relationships with numerous other species. In the great majority of cases however, these mutualistic relationships involve a pair of species, whose co-evolution has been achieved through behavioral adaptation driving positive selection pressures. Humans go a step further, opportunistically and, it sometimes seems, almost arbitrarily elaborating relationships with many other species, whether through domestication, pet-keeping, taming for menageries, deifying, pest-control, conserving iconic species, or recruiting as mascots. When we consider medieval attitudes to animals we are tackling a fundamentally human, and distinctly idiosyncratic, behavioral trait. The sixteen papers presented here investigate animals from zoological, anthropological, artistic, and economic perspectives within the context of the medieval world.