The relationship between animals and humans is more complex today than ever before. In addition to the animals that have served as household pets, and the farm animals that have provided labor and food, countless monkeys, rabbits, rats, and cats have enabled modern scientists to treat and cure humanity's most devastating illnesses. This aspect of animal-human interaction has engendered a bitter enmity between animal rights activists and the biomedical researchers whose work depends on the use (and oftentimes the killing) of laboratory animals. In this work, the author, a veterinarian and sleep researcher argues that humane animal use in biomedical research is an indispensable tool of medical science, and that efforts to halt such use constitute a grave threat to human health and wellbeing. The target of repeated acts of intimidation by anonymous animal rights activists because of his own research, he is himself an animal advocate, and this volume is the culmination of his years spent negotiating the treacherous divide between a legitimate concern for animals and the importance of biomedical research. Drawing on the disciplines of philosophy, history, biology, and animal behavior, he crafts a multi-faceted argument in favor of using animals humanely in research, the center of which is his staunch belief that human interests must be the primary concern of science and society. Along the way, he delves into other human uses of animals in domains such as agriculture, hunting, and education, examining each use along with its philosophical, moral, and ecological implications. The result is a discussion of a charged subject, of the past and present of animals' relationships with humans, and how and why we should be able to use them as we do.