Prevent epidemics and the spread of disease: This is the classic role of public health, although each time it is invoked there is a need to re-negotiate the balance between community protection, social justice and individual autonomy.

Protect against environmental hazards: The limitation of hazardous exposure in the first place is one of the basic approaches of public health.

Prevent injury: The application of Epidemiology to understanding risk factors and the causes of intended and unintended injuries has allowed organized programs to reduce traffic death and injury, occupational injury, food-borne epidemics and other injuries.

Promote healthy behavior: Respecting the autonomy of individuals, it is appropriate to provide education, support and encouragement for for adoption of healthier decisions, actions and lifestyles.

Respond to disasters and assist in recovery: Any disaster markedly increases public health risk by disrupting food, water, medical services and other support systems.

Assure access to health services: This responsibility has become ever more important as the cost of personal care has risen and the numbers of uninsured and underinsured has increased.