Description: For more than 45 years, HRSA-supported health centers have provided comprehensive, culturally competent, quality primary health care services to medically underserved communities and vulnerable populations. Health Care Service Delivery Sites (HCSD) are community-based and patient-directed organizations that serve populations with limited access to health care, including low-income populations, the uninsured, those with limited English proficiency, migrant and seasonal farmworkers, individuals and families experiencing homelessness, and those living in public housing.