One Health is one of the most important movements and emerging concepts in health today. The convergence of the fields of human and animal medicine has the potential to generate novel scientific hypotheses, create effective new therapies and potentially transform how physicians, veterinarians and their patients understand health and disease. Despite this potential, One Health has not yet gained significant awareness or traction in human medical communities. From its inception, One Health, sometimes also called One Medicine, has been piloted primarily by leaders from the world of veterinary medicine. Although the specific term was coined perhaps 10 years ago, comparative medicine has been quietly evident on university campuses with veterinary and medical schools for decades longer. Although a few physicians have played major leadership roles in One Health, in the United States, despite over ten years of the movement's robust growth, many have still not heard of it. Furthermore, physicians with some awareness of One Health often believe it to be primarily and exclusively about zoonotic infections and global health. The much broader scope and potential of One Health as also including comparative physiology and medicine is not being communicated effectively. Consequently, the human medical community remains largely disengaged. This is problematic because without significant engagement from physicians, nurses and other human health care professionals, the potential of One Health cannot be realized. To advance One Health it is imperative that we first understand the roots of under-engagement of the human medical community. This, in turn, can guide the development of novel and engaging opportunities for physician which demonstrate the power relevance of One Health's comparative, collaborative and cooperative approach.[...].