Glastonbury - Stand by for global union

Just over a decade ago, music producer Mark Johnson was making his way to work in New York when he was accosted by an unusual sight: two monks, painted in white from head to toe, rattling out a song in an unknown foreign language. Nonetheless, the event attracted 200 commuters, motionless, rocking on their heels in rapture.

"Everyone there was moved by the performance," Johnson muses. "But I can't imagine that anyone knew what they were singing about. I realised then that music is the key to a better world, and that it was my calling to go out and find as many of these inspiring human moments as possible."

Six years later, in 2004, Johnson started Playing for Change, a multimedia artistic project, which saw the impresario travelling the globe to locations including New Orleans, Barcelona, South Africa, India and Nepal with a mobile recording studio. His aim? Cajoling local musicians into performing the same song – Ben E King's "Stand by Me" – interpreted into their own style, and capturing it on film. While Johnson's mantra was the somewhat nebulous catchphrase of "bringing people together through music", he achieved concrete results. The video (with its "Perfect Day" medley of clips), which featured everyone from Roger Ridley, a Santa-Monica-based street performer, to Manu Chao, went on to garner over 10 million hits on YouTube. It formed part of an album, Playing for Change: Songs around the World, released earlier this year, which charted in the US Top Ten. Not bad for a charity record (the money is being funnelled into a separate foundation, which builds music schools for children). Now, the artists who have performed under the Playing for Change banner are coming together for a unique performance on Glastonbury's Jazz/World Stage. Their limelight-hugging Saturday evening slot promises to be every bit as vibrant and scintillating as the project's work to date might suggest, with cameos from The Magic Numbers and South Africa's Vusi Mahlasela.

"It's the first time we've done Glastonbury and it's like a dream come true for me," says Johnson. "We don't do anything small. For "Stand by Me" we travelled all over the world; this performance will be another opportunity to demonstrate how much you can achieve if you bring together a multitude of cultures and unite them all on stage at the same time."

You can see the album's mainstream appeal; it mostly reworks some well-known pop, reggae and blues classics (the folk standard "Goodnight Irene" features as does "Elder Green Blues" and Bob Marley's "One Love"). Peter Gabriel, Tracy Chapman and Bono also turn up in the recording. And while there is only one non-Western song in the collection, Johnson's trip across five continents is impressive nonetheless. The "Stand by Me" video, once you get over any initial recoil from mawkishness, features astonishing vocals by Ridley and New Orleans' Grandpa Elliott.

Making the film, says Johnson (a rather inspiring, idealistic fellow) involved travelling to Elliott's home city in the aftermath of Hurricane Katrina in 2005. "The city felt sad and desolate, and yet the music never stopped," he says. "The street musicians and music in the clubs kept the city alive and gave it a sense of hope. When we share the struggle of New Orleans with other parts of the world in the context of song, it becomes something everyone on the planet can understand and be a part of." It was a similar story with the producer's visits to South Africa. "When we visited and saw the pain in the aftermath of apartheid, we saw that through music we can raise the issue to a human situation rather than one of race and economics. The South Africans marching down the streets singing in their thousands did more to effect positive change than all the guns and weapons ever did." Johnson's rhetoric is clearly catching. "Because music knows no races, knows no boundaries, it is possible for music to bring peace around the world," says Bhekani Memela, one of the South African musicians who appeared on the record.

Despite Playing for Change's apolitical, populist stance, some of the world's most politically active artists have become involved. Vusi Mahlasela is one of these. A Dylanesque bard christened "The Voice" by his fellow South Africans and "a national treasure" by Nobel laureate Nadine Gordimer, he has traditionally tackled themes like the struggle for freedom under apartheid (he even wrote songs on toilet paper while in solitary confinement, using a pen slipped to him by a sympathetic guard). Why is he involved in something that might force him to bite his lip? "The reality is, while I have written a lot of political stuff in my time, I want to give hope to people," he says, talking from London while preparing for Glastonbury. "Life isn't just about things like struggle, it is about the more positive emotions too. What really appealed to me was the global dimension to what Mark was proposing, you know, love, greed, all these things that I like to talk about in my music are universal feelings. We need to understand more about ourselves if we are to understand each other. I sing in English sometimes to bring people together, too. I also bring humour into the mix – I like to make people laugh, though that can sometimes be difficult to translate."

Johnson now plans to take some of the 50 artists he has collaborated with on a world tour. "The reasons for playing music might differ wherever you go," he concludes. "But the human impact it has is something we share. I believe that when people see what we are doing they will feel more inspired to help each other." To quote the ever-prescient Bob Marley: "One good thing about music: when it hits you, you feel no pain."

Playing for Change headline the Jazz/World stage at the Glastonbury Festival on Saturday 27 June