Jabs for 12-15-year-olds and boosters for the over-50s have been given the go-ahead in Wales.
Third doses will be offered for everyone over the age of 50, all frontline health and social care staff and all those with underlying health conditions.
Boosters for care residents and staff, and NHS staff, will start next week.
Meanwhile, 12 to 15-year-olds who have not had a have vaccine already will be invited to have a single dose.
The decision for young teenagers follows recommendations from senior UK medical advisers that it will help reduce disruption in schools.
It will be up to children and parents whether they decide to take up the vaccines, with the Pfizer-BioNTech vaccine to be used.