This paper explores the changing nature of companion animal-human relationships in Britain over the past 30 years. This period has seen rapid change in attitudes and practices towards companion animals, with notable advances in medical treatment, nutrition, and understanding of non-human animal behavior, as well as re-evaluations of the position of animals within the home. Based upon in-depth interviews with companion animal caretakers and professionals involved in the companion animal industry, we examined these changes in the United Kingdom. Major themes were identified: Humanization, Commercialization, Medicalization, Responsible Companionship, and Alternative Companionship. These changes have had largely positive effects on companion animal health and welfare, but also bring new expectations of the companion relationship, which humans and nonhuman animals may be unable or unwilling to ful-fill. While dominant discourses of responsible companionship prevail, the process of change is ongoing and reflects emerging trends in human society towards diversification and alternative lifestyles.