Why have the strikes been called?Because of proposed changes to pensions for public sector workers, and spending cuts. It's mainly about pensions - as people live longer, the cost of funding public sector pensions is "unsustainable", says the government. It wants most public sector workers to:
- pay more into their pensions
- work for longer
- and accept a pension based on a "career average" salary, rather than the current final salary arrangement which many of them are currently on
Who is taking part in the strike?The TUC is co-ordinating the national day which will see members of unions representing a wide range of public sector workers taking part. They range from podiatrists and radiographers to cleaners and construction workers.
The unions are: The Association of Educational Psychologists, Aspect, Association of Teachers and Lecturers, the Chartered Society of Physiotherapy, the Educational Institute of Scotland, the First Division Association, GMB, National Association of Head Teachers, Napo (family court and probation staff), the teachers' union NASUWT, Northern Ireland Public Service Association, National Union of Teachers, Public and Commercial Services Union, Prospect, the Society of Chiropodists and Podiatrists, the Scottish Secondary Teachers' Association, the Society of Radiographers, UCAC (one of the Welsh teachers' unions), Union of Construction, Allied Trades and Technicians, University and College Union, Unison and Unite.
What impact will I see?At least two million workers across the UK are due to walk out, with more than 1,000 demonstrations expected across the UK.
Organisers expect disruptions to courts, government offices, job centres, driving tests and council services, such as libraries, community centres and refuse collections. Highways Agency staff will be on strike, as will many Police Community Support Officers (PCSOs).
Ministers expect two-thirds of schools to close, and although clinical and medical staff in hospitals will work - the British Medical Association and Royal College of Nursing are not taking industrial action - some staff in hospitals will be on strike which would cause some delays. Thousands of non-emergency operations are likely to be postponed because of the strike.
Delays of up to three hours at immigration are expected at Heathrow as border staff take part in the walk-out. The government has said no border controls will be relaxed to ease queues.
It also says it will not be calling on the Army to step in and it does not believe emergency services will be hit.
Union members will be holding pickets, marches and rallies throughout the country.
Who supports the strikes?Not the government. Ministers insist talks over the pension changes are still ongoing and therefore it is unjustifiable to take action now.
The government says the strikes could cost the UK £500m and lead to job losses. But the unions called the figures "fantasy economics" and accused the government of scaremongering.
Meanwhile, Labour leader Ed Miliband - heckled at the TUC conference for not backing the strikes and attacked by Conservatives for refusing to condemn them - said he was "very concerned about the costs of these strikes". The day before the action he said he hated the "terrible" disruption it would cause, but still would not condemn it.
Has the government changed its offer at any point?Yes. In October, ministers proposed a new offer, saying it would guarantee no-one within 10 years of retirement would have to work longer or see their pension income fall and includes the promise of more generous rates of accrual - the rate at which the value of a pension builds up.
Chief Secretary to the Treasury Danny Alexander said there was "no more money on the table" to settle the dispute and the government had made a "very good offer". There have been suggestions that revised offer could be withdrawn altogether if no deal is agreed by the end of the year.
What if my child can't go to school and I have to work?Parents' rights depend on their employment contracts. If you are an employee, you have the right to take time off to care for a dependant in an emergency - but given that most schools have given several days' notice of closures, this is unlikely to apply in many situations. Prime Minister David Cameron has urged employers to allow staff to bring children to work where possible.
Other options are to
- make use of flexible working arrangements, such as working from home or altering working hours
- take a day's paid leave, or
- ask for a day's unpaid leave
Will parents be able to volunteer to help at schools?Parents who have passed a Criminal Records Bureau (CRB) check for the school in question - for example if they already volunteer there regularly - would be able to help. But CRB checks usually take several weeks.
But during a previous strike, the National Association of Head Teachers warned its members against using volunteers in place of trained staff, even if they have the necessary CRB documentation, because of a host of issues ranging from first-aid training, to insurance, to behaviour management.
How can prison officers take part if they are not allowed to strike?Prison officers are banned from striking because it could compromise the safety of prisons, but peaceful pickets outside workplaces are lawful.
What is happening with public sector pensions?The government wants public sector workers - bar the armed forces, police and fire service - to receive their occupational pension at the same time as the state pension in future. Many can currently receive a full pension at 60. The state pension age is due to rise to 66 for both men and women by April 2020. Under government plans, workers - on average - would have to pay 3.2 percentage points more in annual pension contributions phased in between 2012 and 2014. But low-paid public sector workers on less than £15,000 would not face any increase in contributions and those earning less than £18,000 would have their contributions capped at 1.5%. There have been some claims and counterclaims over what this means for public sector workers.
Why are these changes needed?The Office for Budget Responsibility (OBR) has suggested that the gap between contributions and pensions in payment would double over the next four years to £9bn. One key reason for this is that people are living for longer. The government commissioned Lord Hutton, the former Labour Work and Pensions Secretary, to investigate the situation. Many of its proposals are drawn from recommendations in this report.
What do the unions want to happen?Trade unions have voiced strong opposition to their members paying more in the form of contributions to their pension. It is not clear how opposed they are to changing schemes to a career average version, or to the plans to raising the retirement age to 65 or 66. They were also unhappy that the government announced its plans for pensions while negotiations with the unions were ongoing.
Don't public sector workers get paid less because their pensions are better?This is a myth, according Lord Hutton. His interim report says that "there is no evidence that pay is lower for public sector workers to reflect higher levels of pension provision". Although 85% of public service employees contribute to a pension, he said that these pensions were far from "gold-plated", with the average pension in payment currently at a "modest" £7,800 a year. About half of public service pensioners received less than £5,600 a year. Some private sector schemes are worse than this, but he said that should not affect public sector pensions. In the private sector only 35% of workers sign up for a pension.
How are other countries tackling the pensions shortfall?There are many different systems in place across the world. In France, for example, public sector workers typically retire before 60, but there are plans to bring them in line with the private sector. In Chile, there are mandatory defined-contributions in public and private sectors. Employees pay 10% of their earnings, with top-up benefits for the poorest 60% of pensioners.