The COVID-19 vaccination programme in the Republic of Ireland is an ongoing mass immunisation campaign that began on 29 December 2020 in response to the COVID-19 pandemic in the Republic of Ireland. Ireland's vaccination rollout has been praised as one of the most successful rollouts in the world and was ranked number one in the European Union in terms of its percentage of adult population fully vaccinated, and was also ranked number one in the EU for the number of booster vaccines administered.