The responsibility of local health departments is to protect and promote health, and prevent disease and injury. Public health services are population based – that is, services which are focused on improving the health status of the population, as opposed primary care providers who respond to the treatment of individuals.

To accomplish this mission, public health departments balance three core government public health functions. These functions are essential to the maintenance of population-based services.




  • ASSESS the health needs of the community. To systematically collect, assemble, and make available information on the public health status of the community, in cooperation with others, including statistics on health status, community health needs, environmental health, epidemiologic, and other studies of health problems.
  • INVESTIGATE the occurrence of health effects and health hazards in the community. To systematically develop in collaboration with others in the community, more detailed information on the magnitude of a health problem, duration, trends, location, population at risk, and how best to proceed to prevent or control the problem.
  • ANALYZE the determinants of identified health needs. This is the process of examining etiologic, risk, and contributing factors that precede and contribute to specific health problems or reduced health status in the community. Identifying these factors helps in working with the community in planning intervention efforts for prevention or control.



  • ADVOCATE for public health, build constituencies, and identify resources in the community. This is the process of generating support among constituent groups that address community health needs and issues, establishing collaborative relationships between a public health agency and the public it serves, the government body it represents, and other health and human-related organizations in the community.
  • PRIORITIZE among health needs. To facilitate a community process to rank health needs according to their importance, the magnitude, the seriousness of the consequences, economic impact and community readiness or the ability to prevent or control the problem.
  • PLAN and develop policies to address priority health needs. This is the process by which agencies, working with community constituents and other groups, facilitate the formulated goals and objectives to meet the priority health needs of the community, identify a course of action to achieve the goals and objectives in a way that fosters community involvement and ownership, and is responsive to local needs.



  • MANAGE resources and develop organizational structure. To acquire, allocate influence, resources (people, facilities, and equipment) and to encourage or enable them to meet priority community health needs in the best way possible.
  • IMPLEMENT programs. Work with other organizations, agencies and individuals to assure the implementation of programs in the community that fit community priorities. Work with the community to change community policy, practice or mores.
  • EVALUATE programs and provide quality assurance. This is a process of continuous inquiry to determine the efficiency and effectiveness of efforts so that corrections can be made to improve activities and outcomes.
  • INFORM and educate the public. This is the process of informing the community about health problems, the availability of services; gaining the attention of individuals, high-risk groups, and constituents concerning public health issues; and providing health education to help develop beliefs, attitudes, and skills conducive to good individual and community health.