Q&A: Doctors' industrial action
Doctors in the UK have taken part in their first industrial action for nearly 40 years. Here we look at why the medical profession is so angry.
Why was the action taken?
The dispute is over pensions. Doctors are angry that the government is changing their pension scheme just four years after a new deal was reached.
They feel the government has broken promises it made in 2008, although of course there has been a change of administration since then.
The British Medical Association - the doctors' trade union - has argued that contributions are going up too much and that asking doctors to work until they are 68 is wrong and could harm patient care.
The BMA balloted its members. Of those balloted, half responded with the majority voting in favour of action.
Among GPs, 79% were in favour, for hospital doctors the figure was 84%, and among junior doctors it was 92%.
What does the government want to do with their pensions?
It has argued they are not sustainable, despite the new scheme only being four years old.
It says that doctors - like the rest of us - are living longer and so need to contribute more over a longer period of time.
For the highest earners - those earning more than £110,000 - contributions will rise by half to above 14%. The BMA has argued that is nearly twice the amount the highest-paid civil servants have to contribute.
They will also have to work for longer. Doctors in the 2008 scheme currently have to work until they are 65, but under the new system that will rise to 68 for them to be entitled to their full pension.
Those in the old scheme and close to retirement are still being allowed to retire at 60.
The government has argued that the new scheme is still generous. A doctor starting work in 2015 would see their annual pension reach about £68,000 a year if he or she worked until 68.
All doctors will also be put on career-average schemes - most are on final salary arrangements at the moment with only GPs on career-average ones.
What about other NHS staff?
It was only doctors that took part in the action.
Unions representing a host of health professionals, including paramedics, admin staff and porters have already taken part in strikes over pension changes.
But the Royal College of Nursing, one of the most influential voices inside the NHS alongside the BMA, has yet to decide what it will do.
It has held a ballot where the majority rejected the government's pension changes, but the turnout was low.
Meetings have been taking place between unions over what to do next - although much will depend on what the BMA does next.