Firefighters in England and Wales will go on strike again in a row with the government about their pensions.
Members of the Fire Brigades Union will stop work between 6:30pm and 11pm today, and for two hours on Monday.
They'll still go to any major fires, but fire bosses advise people to put off home firework displays to Saturday night, or go to an organised event.
The government says the strike action is completely unnecessary and will harm the reputation of firefighters.
There have been previous strikes earlier this year as the row goes on, with the union concerned about government plans to raise the age firefighters need to retire.
At the moment firefighters can retire at the age of 55, but the government wants to raise that age to 60.