Domestication is a set of processes that requires active reconfigurations of interspecies relations, environments, and technologies. In this view, both ethnographic and historical sources help us track the exact ways that domestication as a practice actively reveals and conceals relations of power among people and between people and other animals. Two pertinent cases—training rats in Tanzania to detect landmines and releasing mosquitoes to deter the transmission of pathogenic viruses in Brazil—take place in contexts where animals are being modified to achieve certain developmental, medical, or humanitarian goals. These animals, like any in the history of domestication, breach boundaries, crossing wild and domestic categories, in these cases at the moment and experience of being bitten. These moments draw our attention to the stakes involved in thinking about domestication.