 A distinct set of questions of justice arises because promoting public health involves a significant commitment to the prevention of disease and injury. This commitment to prevention is often seen as a defining feature of public health institutions, even though public health agencies and services also engage in diagnosing and treating illnesses, with all the attendant clinical services that those activities  require.[8]  Indeed, national health systems are increasingly understood to include both preventive functions and the delivery of personal medical services. Often these functions and services are integrated under a common political or administrative structure. Depending on the specific context in which population health is to be promoted, separating population health services and functions from personal medical care services and functions may or may not make sense. That said, policies and programs whose aim is to prevent illness and injury are paradigmatically the territory of public health. Certainly, no other social institution is recognized as so clearly having this remit.