Thailand has been fighting COVID-19 longer than any country in the world except China – after isolating the virus on January 13, 2020. Thailand’s public health priorities in 2020 focused on limiting the spread of COVID-19, reducing morbidity and mortality associated with the virus and maintaining essential health services for the population. Vaccination offers Thailand another mechanism to combat COVID-19. The Ministry of Public Health (MoPH) is planning to immunize between 50-80% of persons living in Thailand against COVID-19 in 2021. This is planned out in phases as doses of vaccine will initially be limited. Healthcare workers, other essential workers, the elderly and those with chronic medical conditions have been prioritized for vaccination. Clear and accurate communications around the benefits and safety of the vaccine will be critical as immunization is extended to the general population, including migrant populations. Monitoring the progress of COVID-19 immunization will also be important to support policy and safety. This project aims to protect the health of people living in Thailand by strengthening communications for and monitoring of mass immunization campaigns against COVID-19.