Donkeys maintain a special status in the minds of the UK animal-owning population in that, although they are physically large animals, they are usually regarded by their owners as companion animals in the same vein as dogs and cats. This dichotomy can bring about clinical challenges rarely seen with other species. Although most conditions affecting donkeys are similar to those occurring in horses, donkeys by their very nature can behave differently in the face of disease. Hence, some clinical presentations that would ordinarily be dismissed in other equids must be considered as medical/surgical emergencies in the donkey. This article, the first in an occasional series discussing the clinical approach to problems in the donkey, describes the options for castration, and offers practical advice on how to avoid some common pitfalls and potentially fatal complications that are specific to this species.