This book discusses how bioethics can be advanced and expanded. It explores the possibility to find an approach to bioethics that covers all One Health approaches, i.e. One Health, EcoHealth, Planetary Health or One Welfare, each with their holistic and diverse perspectives. Although some attempts exist to find such an ethics of One Health, this is still very much novel ground. From an analysis of the nature of scientific aims and goals of One Health approaches, this book describes and expands on the variety of ethical issues that emerge in this context. Analyzing previous attempts to establish an ethics of One Health, this book shows that the complexity is greater than what is sometimes suggested. Some issues might be solved using a more traditional perspective on bioethics but other issues need a new take on bioethics. This book analyses what is needed for a pluralistic ethics that covers different species - humans, animals, plants - as well as different levels - individual, population, ecosystem. It discusses whether it is possible to find a bridge between versions of anthropocentric, zoocentric, biocentric and ecocentric ethics. Also, due to the trans- and interdisciplinary nature of One Health approaches, it discusses how this ethical framework will relate to different value and ethical systems around the globe. As a result, this book is a roadmap for future discussions and research in this emerging field, proposing an ethical framework for One Health approaches.