British Army soldiers are helping to establish 80 new Covid vaccine centres across Scotland.
The Ministry of Defence (MoD) said 98 soldiers were being deployed to identify suitable sites and aid deliveries of the vaccine.
More than 200,000 people in Scotland have already received their first dose.
The UK's vaccine deployment minister Nadhim Zahawi said the Army would be setting up the sites before conducting a "smooth handover" to NHS Scotland.
The soldiers are from the Royal Army Medical Corps and Leuchars-based Royal Scots Dragoon Guards.
The Scottish government has said it wanted to vaccinate the over-80s, care home residents and staff, front-line health workers and social care workers by the beginning of February - about 560,000 people.
First Minister Nicola Sturgeon said people in the over-70 age group would start getting invitations for appointments "literally over the coming days".
A total of 264,991 people have now been given a first dose of a coronavirus vaccine in Scotland.
Ms Sturgeon said 80% of care home residents had now been vaccinated, with the programme for all those over 80 now "picking up pace".
She said Scotland was working to the same targets as the rest of the UK nations, and was "on track" to hit them.
At the weekend the British Medical Association said there had been issues for some GPs receiving supplies of the vaccine in Scotland.
The first minister said she had taken part in a call with manufacturer AstraZeneca last week, and said that while manufacturing and supply were "a bit bumpy" at the moment "they expect them to level out and become much more sustainable at a certain level".
She said the aim was to get all adults vaccinated "absolutely as quickly as we can".
Members of the Royal Scots Dragoon Guards have already been used to run mobile Covid testing centres in Scotland.
The deployment of soldiers to help with the continued vaccine rollout is part of the "largest peacetime resilience operation" ever undertaken by the UK Armed Forces, the MoD said.
Organised into 11 teams spread across Scotland, they will be supporting NHS Scotland for the next 28 days.
Health Secretary Jeane Freeman said it was the largest mass vaccination programme Scotland had ever undertaken and said she was very grateful for the support of the armed forces.
"This deployment will see 11, eight-person multi-disciplinary teams providing fast and assured site preparation over a four-week period, identifying and operationalising vaccine sites before handing them over to NHS Scotland staff," she said.
"Vaccination is a vital tool in our work to suppress the virus to the lowest possible level in Scotland, but other measures including testing remain absolutely vital, which it is why it is so essential people continue to follow the restrictions currently in place while vaccine delivery is rolled out across the country."
What will the soldiers be doing?
The MOD said the soldiers would be using their "logistical, organisational and clinical expertise" to establish the vaccine centres, before handing them over to NHS Scotland to deliver the vaccination programme.
The military teams will organise car parking and traffic flow, as well as setting up patient recording methods.
They will also help with vaccine delivery to each of the 80 sites as well as helping to prepare storage for medicine and equipment.
Three vaccines have now been approved by UK regulators, developed by Pfizer-BioNTech, Oxford-AstraZeneca and Moderna.
They have been purchased by the UK government, with Scotland being given a share based on its population size.
Doses of the Pfizer and Oxford vaccines are currently being given, with supplies of the Moderna vaccine expected from early April.
The soldiers helping with the vaccine effort will be controlled by Joint Military Command staff in Stirling.
There are a further 32 UK military planners working in support of the Scottish government team in St Andrews House, Edinburgh, and across Scotland's 14 health boards.
The military has already been used for medical evacuations of patients sick with Covid from Shetland, Orkney and Arran.
Ms Sturgeon thanked the military for their help with logistical matters, noting they had also been involved in distributing PPE supplies and setting up the NHS Louisa Jordan hospital in Glasgow.