One of the models for the role of local health departments is called the home rule or local autonomy model, in which authority is delegated from the state to the local health department. In this model, the local health department has a great deal of autonomy in setting its own structure and function.

The following are the functions of a local health department:

- Immunizations for individuals not covered by the private entities,

- Surveillance of communicable disease and initial investigation of outbreaks,

- Communicable disease control often including at a minimum tuberculosis and syphilis case finding and treatment,

- Inspection and licensing of restaurants, environmental health surveillance,

- Coordinating public health screening programs, including newborn and lead screenings,

- Tobacco control programs, public health preparedness and response to disasters.

a1 = unhealthy

a2= healthy

a3= healthy