Vaccine safety monitoring is ensured at the national, regional, and global level. As is standard practice in all national immunization programmes, WHO supports the set up of safety monitoring systems for COVID-19 vaccines in every country. After a COVID-19 vaccine is introduced in a country, WHO works with vaccine manufacturers, health officials and other partners to monitor for any safety concerns on an ongoing basis. Specific safety concerns that may arise are evaluated by WHO and an independent group of experts (the Global Advisory Committee on Vaccine Safety, or GACVS) in conjunction with the relevant national authorities.