The Centers for Medicare & Medicaid Services (CMS) published an emergency regulation requiring staff vaccinations for COVID-19 across a variety of Medicare and Medicaid-certified health care providers. These requirements apply to approximately 76,000 providers and cover over 17 million health care workers across the country. CMS is responsible for establishing minimum health and safety standards for many provider types; these are known as Conditions of Participation, Conditions for Coverage, or Requirements (collectively, “standards”). Facilities must meet these standards to receive payment for services provided to Medicare and Medicaid beneficiaries. CMS maintains oversight of these standards for a significant portion of the nation’s health care system, including hospitals, End-Stage Renal Disease (ESRD) facilities, home health agencies, and a number of other health care settings. This emergency regulation requires staff vaccinations across 15 specific health care providers participating in the Medicare and Medicaid program to address the clear and present need to protect patients against COVID-19.