Hundreds of thousands of public sector workers across a range of jobs have begun a national day of action in disputes over pay and conditions.
Strikes have been an almost daily occurrence throughout January, while several walkouts are already planned for February and into March.
Staff across transport, education, health and government sectors are demanding more pay as the nation continues to grapple with a cost of living crisis.
Watch: Biggest day of strikes in a decade will involve up to half a million workers
In November 2022, the most recent date for which data is available, 467,000 working days were lost to labour disputes – the highest since November 2011.
Among the upcoming strike dates, today stands out – a national day of action that will see walkouts from a range of different professions.
When is the national day of action?
A widespread day of strike action is taking place today. It is the biggest day of action since 2011 when well over one million public sector workers staged a one-day strike in a dispute over pensions.
Who is striking today?
So far, teachers, train drivers, civil servants, university staff, bus drivers and security guards in seven trade unions have confirmed co-ordinated walk-outs.
Why are the strikes happening?
Most of the workers going on strike are doing so because of pay.
Most state school teachers in England and Wales were given a 5% pay rise last year. However, unions say this was effectively a pay cut because of inflation is more than 10%. Teachers in Scotland have rejected a 5% pay rise.
Rail workers are also in dispute about their pay, as well as job cuts and changes to working terms and conditions.
Civil servants are asking for a 10% pay rise, as well as better pensions, job security and no cuts to redundancy terms.
University staff want a pay rise either 2% above RPI inflation, or 12%, whichever is higher.
Outsourced security guards at UCL, represented by the IWGB, are demanding a pay rate of £15 an hour, union recognition and an end to outsourcing of services.
Which unions are involved?
In England and Wales, teachers who are members of the National Education Union (NEU) will go on strike over pay.
It is the largest eduction union in the UK so the disruption to schools is expected to be widespread. More than 23,000 schools in England and Wales are expected to be affected.
In Scotland, teachers from the Educational Institute of Scotland (EIS) will also be on strike in Clackmannanshire and Aberdeen as part of an ongoing pay dispute.
Train drivers who are members of the Aslef union will also be on strike on 1 February, which will affect most of the train companies in England. Drivers from the Rail, Maritime and Transport (RMT) union will also walk out.
Meanwhile, about 100,000 civil servants across 124 government departments and other bodies will strike over pay and conditions on the same date.
This will include staff at the Department for Work and Pensions (DWP), the Driver & Vehicle Licensing Agency (DVLA) and the Department of Health and Social Care (DHSC).
About 70,000 members of the University and College Union (UCU) will go on strike at 150 universities across the UK, as part of 18 days of walkouts between February and March.
Bus drivers who work for Abellio in London are also going on strike today.
The date has also been scheduled for a nationwide protests against the government's controversial new anti-strike law.
What is the new anti-strike law?
Earlier this month, MPs voted to give the Strikes (Minimum Service Levels) Bill a second reading in the House of Commons.
The controversial legislation would require minimum levels of service from ambulance staff, firefighters and railway workers during industrial action, although unions and opposition MPs have condemned the proposals as unworkable.
Details of the minimum service levels which will need to be maintained during strikes have yet to be set out, and the government says it will consult on this.
Business secretary Grant Shapps said: “We want constructive dialogue with the unions and the public has had enough of the constant, most unwelcome, frankly, dangerous disruption to their lives.”
Labour deputy leader Angela Rayner criticised the bill as “one of the most indefensible and foolish pieces of legislation to come before this house in modern times”.
She added: “It threatens teachers and nurses with the sack during a recruitment and retention crisis."
What other strikes are happening?
Aslef and RMT train drivers will also walk out on Friday 3 February, while teachers in the NEU are also scheduled to strike across England and Wales again on 15 and 16 March, with regional strikes planned for 14 February, 28 February, 1 March and 2 March.
On 6 and 7 February, nurses from 73 Trusts in England will strike in an escalation of industrial action by the Royal College of Nursing (RCN).
What has the government said?
Downing Street said widespread strikes on February 1 will likely cause “significant disruption” to the public.
The prime minister’s official spokesman said: “We’re in no doubt that this strike action, some of which will fall on the same day or days, will cause significant disruption to the public – whether it’s children having their education disrupted or the public trying to go about their daily lives on their commute.
“We don’t think it’s the right course of action, we continue to call unions to step away from the picket lines and continue with discussions.”
Watch: Aslef union train drivers announce two more strike dates