Up to half a million British teachers, civil servants, train drivers and university lecturers will strike on Wednesday in the largest coordinated action in a generation which the government says will cause widespread disruption.
The mass walkouts will see schools close, the military on standby to help at Britain's borders, and no rail services running across much of the country.
Union leaders estimate up to 500,000 people will take part, the highest number for at least a decade, and there will be rallies against a planned new law to curb strikes in some sectors, a proposal they argue will poison relations further.
"After years of brutal pay cuts, nurses, teachers and millions of other public servants have seen their living standards decimated – and are set to face more pay misery," said Paul Nowak, General Secretary of the Trades Union Congress (TUC), the union umbrella group.