The management of wildlife in the United States and Canada, including the monitoring and maintenance of the health of wildlife populations and the ecosystems on which they depend, are conducted under a set of principles that aim for sustainable use. This set of principles is known as the North American Model of Wildlife Conservation (the Model), and it guides wildlife management and conservation decisions in both countries. The purpose of this perspective is to highlight how wildlife health is an important part of the Model and is vital to its future. It is proposed that wildlife health and the Model support one another. First, the history and fundamental ideas of a public trust that shaped the Model are reviewed. Next, wildlife health is defined and examples are offered that highlight how the Model supports wildlife health and how health affects the Model, as well as the limitations or threats if one moves away from the Model's defining principles. Finally, controversies surrounding the Model are reviewed and a perspective on the future is offered, based in large part on the work of Aldo Leopold. Leopold's thinking about health of the land and its organisms was well ahead of its time, and the scientific underpinnings of his writings in making the case for wildlife health and the Model are recounted. As a simple addendum to Leopold's land ethic, a plea for a health ethic is called for, whereby healthy wildlife and healthy landscapes are an obligation of the Model and modern society because health "tends to preserve the integrity, stability and beauty of the biotic community."41.