Striking cleaners and caterers at the Department for Business, Energy and Industrial Strategy (Beis) have entered the fifth week of an indefinite strike over low pay and outsourcing.
The members of the PCS union at the Beis headquarters in central London are demanding the London Living Wage of £10.55 an hour.
The workers, employed by outsourcers ISS and Aramark, are also demanding to be brought back in house.
Strikers have held lively picket lines outside Beis every week since the strike began.
They have also visited other PCS branches, and joined striking cleaners at HMRC tax offices in Liverpool and Bootle.
But bosses so far appear to have refused to agree even to talks.
As strikers said during their visit to Liverpool last week, low pay and outsourcing are problems facing workers across Britain.
Their fight should be turned into a high-profile cause that all trade unionists should support.
It could become a focus for the fight against low pay and outsourcing everywhere.