Feathers flew at the weekend as thousands of people worldwide, from New York to Hong Kong, celebrated International pillow fight day.
The annual event, which started in 2008, had fights planned in 115 cities in 39 different countries with volunteers organising the event through social-networking sites.
A few rules were put in place to stop injuries and keep things pleasant - use soft pillows, don't hit anyone holding a camera and remember to take off your glasses.
In London's Trafalgar Square, people came dressed in pyjamas, dressing gowns and fancy dress to take part. Most carried feather-filled pillows that exploded as they fought.
New York's Union Square became a bedding battleground as thousands gathered to join in the event, which was started by The Urban Playground Movement.
The Urban Playground Movement's guide for would-be organisers includes the advice not to use parks - both to avoid littering and because 'most events in parks are boring' - and never to ask permission.
"This may change in the distant future if we witness some kind of crackdown against free events and interventions, but in the meantime, it is very unlikely that anybody will say yes," they say.
"We must also remind you: the "permit culture" we citizens witness in city halls around the world is perhaps the single largest barrier to experiencing the full richness of public life in the cities we live in.
"Do not ask for permission, public assembly is a human right."