Some of Scotland's best-known galleries and museums are closed due to a 24-hour strike by four different unions over pay and conditions.
The walkout has closed the Kelvingrove Museum, the Burrell Collection and the People's Palace, which are all run by the charity Culture and Sport Glasgow.
The dispute is over the organisation's bid to freeze wages and cut overtime.
The Unison, Unite, GMB and Bectu unions said they had no other option after talks to resolve the dispute failed.
Culture and Sport Glasgow is a charity which runs various facilities which used to be run by the city council.
As well as museums and galleries, it is also responsible for sports centres, community centres and libraries.
The charity said that as a result of the strike, all museums and community facilities would be closed on Friday.
Three libraries are open with 12 leisure and recreation facilities also open or partially open.
Unison's Glasgow branch secretary Brian Smith said all four trade unions involved in the action had been left with no other choice.
"The trade unions have attempted to negotiate to persuade Culture and Sport Glasgow not to carry out these attacks," he said.
"However, workers have been left with no option other than to use strike action in an effort to defend their pay and conditions.
"Our members provide culture and sport services across Glasgow and recognise the wide disruption that strike action will cause."
The four unions involved in Friday's strike are also planning a second day of action on 6 May.
Some community centres due to be used as polling stations could be affected by the action, but Culture and Sport Glasgow insists no polling stations will be closed.
The charity said it was disappointed that Friday's action was going ahead.
A spokesman for Culture and Sport Glasgow said: "Around one-in-seven of our staff voted for strike action and the trade unions are fully aware that the public sector is not immune from the current financial crisis.
"We have consistently made it clear that our priority is to protect both services and jobs.
"In order to make the savings necessary to achieve this, we must change the way we work - or be forced to consider job cuts."