More than 7.1 million people in the UK have had at least one dose of a vaccine to protect against Covid-19.
All have been shown to safe and effective in trials. Two doses are needed to offer the best protection and these will now be 12 weeks apart.
When will I get a vaccine?
Vaccines are being given to the most vulnerable first. A list of nine high-priority groups which covers about 32 million people - including 90-99% of those most at risk of dying - is being followed:
- Residents in care homes for older adults and their carers
- 80-year-olds and over and frontline health and social care workers
- 75-year-olds and over
- 70-year-olds and over and clinically extremely vulnerable individuals
- 65-year-olds and over
- 16- to 64-year-olds with serious underlying health conditions
- 60-year-olds and over
- 55-year-olds and over
- 50-year-olds and over
NHS frontline staff, care home residents and workers, and the over 80s have been the first priority. More than 75% of over-80s and older care home residents in the UK have now been vaccinated.
In many areas, people over 70 and those considered clinically extremely vulnerable are now being vaccinated although different regions of the UK are progressing at different speeds.
Are two doses needed?
All the approved vaccines require two doses to provide the best protection.
Initially, based on how the jabs were tested in trials, people were told they would get the second dose three to four weeks after the first.
But to ensure as many people as possible are protected from becoming seriously ill or dying with Covid-19, the UK's chief medical officers decided to give as many people as possible a first dose.
So the gap between doses was extended to 12 weeks.
This decision was based on how other two-dose vaccines work and some evidence of a good level of protection from around two weeks after first doses of both jabs - although how long this lasts has not been fully tested.
Some doctors have been critical of the decision, fearing it will make the Pfizer vaccine, particularly, less effective.
Few countries have followed the UK's example, as yet, and the World Health Organization has recommended a gap of up to six weeks only in exceptional circumstances.
When will police and teachers be vaccinated?
From spring, the second phase of vaccination will focus on the rest of the adult population - mainly under-50s, who are much less likely to be ill with Covid-19.
Teachers, transport workers, supermarket workers and the military could be prioritised.
Education Secretary Gavin Williamson recently said he wanted school staff to be a "top priority" for the vaccine in the next phase of the rollout.
Metropolitan Police Commissioner Dame Cressida Dick has said she was "baffled" that frontline officers weren't prioritised.
Home Secretary Priti Patel says work is under way to move "police, fire and frontline workers" higher up the queue.
Where will I get a vaccine?
Thousands of vaccination sites are operating:
- in hospital hubs for NHS staff and older patients
- in thousands of GP surgeries
- in care homes for workers and older residents
- in some pharmacies
- in sports stadiums and conference centres acting as major vaccination hubs
You'll be invited to book an appointment as soon as it's your turn, by phone or letter.
Can different vaccines be mixed?
The official guidance says everyone should get the same vaccine for both doses.
In very rare circumstances - if only one vaccine is available, or it's not known which was given for the first dose - a different vaccine can be used.
How many vaccine doses are there?
In total, the UK has ordered 100 million doses of the Oxford-AstraZeneca vaccine and 40 million of the Pfizer vaccine.
Another 17 million doses of the Moderna vaccine are expected in the spring.
The aim is to reach two million vaccinations a week, with everyone in the top four priority groups (up to 15 million people) given a first dose by mid-February.
This requires a steady supply from manufacturers and the required quality checks being carried out, which can take weeks.
Will everyone be vaccinated and which will I get?
The aim is to vaccinate as many people as possible over the age of 18.
The vaccines have not been tested in children so they won't get them until more research has been carried out.
Getting a Covid vaccine is not compulsory because experts say this wouldn't help create public confidence.
The government has so far ordered seven different types of vaccine and expects to receive 367 million doses in total.
If everyone needs two doses, that would certainly be enough for every adult in the UK.
Experts have not specified that any one group should get a particular vaccine.
What about people with allergies?
A very small number of people have experienced a severe allergic reaction - known as anaphylaxis - when vaccinated with the Pfizer BioNTech vaccine.
The UK regulator says anyone with a history of severe reactions to food, insect bites or a drug or vaccine can safely receive either vaccine as long as they are not allergic to any ingredient in the vaccine.
You should discuss any medical history of serious allergies with your healthcare professional before being vaccinated.
Most people will not be affected in any way, although mild side-effects - which are common with any vaccine - are possible.
I'm pregnant - can I be vaccinated?
Vaccination should only be considered for pregnant women when the potential benefits outweigh any potential risks.
This may be where the risk of exposure to coronavirus is high and cannot be avoided, or where underlying health conditions mean a high risk of Covid complications.
There are no specific safety concerns with the vaccines - but they were not tested on pregnant women.
Women who are breastfeeding can be given either vaccine.
Can I pay to be vaccinated sooner?
No - this vaccine is being rolled out free to people via the NHS. You can't jump the queue by paying.
Should I leave a gap between the flu and Covid vaccines?
If you're eligible for a flu vaccine, you should get it as soon as possible, particularly if you will also be in a high-risk priority group for a Covid jab.
At its last meeting, the Joint Committee on Vaccination and Immunisation (JCVI) recommended leaving at least seven days between the vaccines.