Organisers of the World's Big Sleep Out, which began on a small scale in Edinburgh in 2016, said 52 cities participated in this year's event, from Brisbane to Los Angeles.Fundraisers in London's Trafalgar Square were treated to a bedtime story by Dame Helen Mirren, while Will Smith did the honours in New York's Times Square.As well as raising funds, the event encourages people to reflect on the plight of the homeless and displaced, and this year it teamed up with Unicef and the Malala Fund.Actor Brian Cox opened the sleep-out in Edinburgh's West Princes Street Gardens, saying the time has come to address homelessness.He told the PA news agency: "It has gone on long enough. We have just accepted these norms which shouldn't be accepted."I remember Cardboard City in Waterloo, I used to rehearse there, at the National Theatre, I walked past there and it would be a few people sleeping out, but by the time of the end of my rehearsals it was about 250.
"It's just accepted as a norm, and it's worldwide - it's an example of worldwide lack of care that we've allowed this situation to get out of hand.
"It has to be curbed, I don't think you'll ever get rid of it but it has to be curbed."The Dundee-born actor said of his home city: "Dundee has elements of it. The problem in Dundee has been, of course, people have been ignored for too long, and it's the rise of addiction, drugs addiction."Again these are people that we've not known how to take care of, and they don't really know how to take care of themselves, and that's the tragedy of it."Dundee has always been a tough city in that way."It's the city that Churchill cursed when he was kicked out, it's sort of got itself up and it's really done a lot, but there's still this kind of core at the centre of it which needs huge attention."The campaign was founded by Josh Littlejohn, who started the sandwich shop Social Bite in Edinburgh to offer employment to homeless people.The Rose Street premises has been visited in recent years by Hollywood stars Leonardo DiCaprio and George Clooney.The charity organised a sleep-out in 2016 with 270 participants and the event has grown each year in Scotland.Mr Littlejohn said: "What the incredible 60,000 people who slept out all over the world have done tonight is to shine the spotlight on this global issue and show that we care."I am truly blown away by the response to our campaign and sincerely grateful to every single person who has given up their beds tonight to raise the funds and awareness needed to make an impact."I hope that what happened in this campaign demonstrates a clear mandate for political action to tackle the homelessness crisis to whoever ends up in government in a few days' time."Cities taking part in The World's Big Sleep Out include Chicago, New Delhi, Newcastle, Dublin, Belfast, Madrid, Barcelona, Brussels, Cardiff and Santiago.