What are the perceptions of population health, and how do you define it to move forward on any common action agenda of policy, management, teaching, or research? The author asks a series of questions to clarify the ambiguities around the population health concept, beginning with defining "health" as more than the absence of disease, but less than the breadth of complete well-being. Such a framework requires an operational measure of population health outcome that goes beyond quantity of life (mortality) to add extra dimensions. In other words, the goal is not only to purchase life years, but life years at some level of quality. The article provides an argument for the importance of some aggregate measure of health outcome, such as Health Adjusted Life Expectancy (HALE), as a management tool for purchasing populations health.