By Tim Weber
Business editor, BBC News website, in Davos
The World Economic Forum seems to be a star-studded event this year
Lucky the charity that has the patronage of a global superstar.
Media attention is guaranteed, donors' wallets open and all is well. Or is it?
Let's take a much celebrated example of Davos charity.
A year ago, Hollywood megastar Sharon Stone attended the World Economic Forum and heard the Tanzanian president explain that every year a million people were dying of malaria because they lacked basic precautions like bed netting to keep mosquitoes away.
Ms Stone stood up, pledged $10,000 and challenged business people to match her donation. Within 10 minutes more than $1m was in the bag.
Err ... not quite. Only a minority of the pledges was honoured; thankfully a UN body made up the shortfall.
But "should we rely on Ms Stone's instincts to determine a worthy cause" in the first place, asks Xavier Sala-i-Martin, economics professor at Columbia University.
Every year diarrhoea is killing more people than Malaria, he says - so could the UN organisation have used the money for an even more urgent cause?
So what are the risks of "Celebrity Inspired Action"?
It was the question put to a panel at the World Economic Forum in Davos, itself sporting two real-life celebrities ¿ actor Michael Douglas and singer Peter Gabriel - as well as a crown prince.
Of course some cynicism will be justified, acknowledged Mr Gabriel. There will be celebrities who fall for the wrong cause, and those who jump on a bandwagon trying to revive their flagging careers.
But celebrities can do some good, and it was not just the celebrities who said so.
Hollywood stars broke the silence surrounding Aids, but it was the so-called "Princess Diana effect" - she held hands and hugged Aids patients - that persuaded millions to accept Aids patients.
"That had more effect than any billboard could have had," said Peter Piot, director of the United Nations programme on HIV-Aids.
Reaching the unconverted
Also, when "Women for Women", a charity that helps women in war zones, tried to get media attention for its cause it took Queen Rania of Jordan to open Hollywood's doors and Oprah Winfrey to open America 's wallets.
Without celebrities, that cause would have gone unheard; women raped by soldiers in Rwanda would have been left without help.
Sharon Stone was the big celebrity draw at Davos last year
Hollywood actor Michael Douglas makes a simple equation: "If I write for the op-ed [editorial] pages I preach to the converted.
"If I get the subject onto the entertainment pages, it allows me to share a subject matter with an audience that may not be aware of it."
Professor Sala-i-Martin agrees that celebrities can do some good.
But he is still worried that as a result some aid flows are not based on rational decisions, but the whims of a superstar.
A star, he says, that is not accountable to anybody.
Peter Gabriel agrees: "Maybe we need to use the internet as a celebrity judgement aid."