Regions within every Arizona county have received at least one of three federal designations:
- Health Professional Shortage Area (HPSA).
- Medically Underserved Area (MUA).
- Medically Underserved Population (MUP).
These shortage areas are determined and managed by the Bureau of Health Professions within the Health Resources and Services Administration who identify geographic areas or specific populations within those areas that lack adequate health care resources. The resources available in a given area are evaluated based on physician supply relative to population size — although numerous other factors are also considered.