An inside-out concrete house appears in an East End park; hundreds of voices in a Babel of languages murmur stories of encounters with UFOs in a disused Baptist chapel; faces glimmer mysteriously on trees and walls around a Soho square; a man systematically lists and then breaks down every one of his possessions on a "destruction line" in an empty department store... all examples of 'angels' making the impossible possible. Artangel, the prime mover behind these extraordinary events, is a unique organisation. It commissions installations that are often literally wonder-ful, that move and inspire by creating a strong visual impact that is remembered with pleasure and interest long after the work has vanished. Artangel functions outside the world of galleries and auction rooms, and you're unlikely ever to want one of their products to hang on your wall; indeed few, if any, of them are hangable or ownable. If you've ever wondered, as I had, how quirky and short-lived artworks like Rachel Whiteread's House or Susan Hiller's Witness are commissioned, made and paid for, then Artangel provides one answer.

It is a creative combination of the vision and energy of its co-directors, James Lingwood and Michael Morris, with public and corporate funding and (Artangel's unique extra component) the 'company of angels' – art lovers willing to commit a few hundred pounds a year to help the extraordinary happen. Few of us can be a Medici or a Saatchi, but Artangel enables people (like me, for instance) who are not fabulously rich to become patrons and part of an artistic adventure.

Though reponsible for contemporary, often startling and sometimes unsettling, artworks, Artangel distances itself from the Young British Artist / Turner Prize / conceptual art scene, a scene that has come under fire recently for its banal ideas and lack of visual interest, and which James and Michael think has become "a bit of a circus", with the media and personalities distracting from the art. "The Turner-YBA thing is all a bit tired and parochial," says Michael, who claims, with some justification, that Artangel works are very different – real experiences that affect one's consciousness and live on in the memory. "Our installations are essentially a physical, visceral, aural experience," he says. "They aren't 'conceptual art', though of course every work begins with some kind of concept." It usually ends in an experience for which the only appropriate response is "Wow!" rather than an overly intellectual one.

Every work is a collaboration between the artist's concept and the practical enabling work of Artangel, which finds sites, raises funds, and deals with the logistical problems. "We've never commissioned a work that didn't have problems or miss deadlines," says Michael, who doesn't seem unduly bothered by this. Nor is he worried by the impermanence of most of their commissions, indeed says that the temporary nature of the installations is one of their virtues, particularly for the owners of the spaces they borrow. Few local authorities or landlords would allow Artangel to take over an open space or empty building indefinitely, but some will lend somewhere for a short spell.

Fortunately Artangel's patrons are an open-minded lot, willingly buying into a world where risk and the unexpected are part of the attraction. James and Michael, perhaps diplomatically, have nothing but praise for their funders, who "allow them to be different" and "enjoy the journey into the unknown". They have worked hard to earn this trust, and this year celebrate ten years of ground-breaking projects. In the early '90s, they joined a tiny privately financed commissioning organisation which offered artists the opportunity to 'intervene' in areas of social concern; they found new funding and trustees, developed relationships with artists, and built Artangel into the highly visible presence it is today. They have retained the original idea of connection with place – every installation has a strong relationship with its site, indeed is often completely dependent on it – but moved away from social themes to more imaginative and inspiring 'interventions' – events that make us look at places in new ways.

That said, one of their most recent events, The Battle of Orgreave, which recreated one of the key incidents of the miners' strike of 1984, was intensely socially committed. When asked which has been their favourite project they say "The last one, it's always the last one" and when asked which was the most troublesome they laugh and give the same answer. Certainly the logistics of a re-enactment in South Yorkshire of a violent clash between miners and policemen, using a cast of hundreds, must have caused headaches still fresh in their minds. But they were pleased with the results and looking forward to the film of the event on Channel 4 this year.

Another memorable project was last year's Breakdown by Michael Landy. Widely seen as an ironic critique of consumerism, Landy's methodical destruction of everything he owned, from his car to every last sock and photograph, brought a whole new audience for art into the former C & A store in Oxford Street. Attracted by the intriguing quasi-industrial spectacle visible from the pavement outside, they stayed to speculate on the amazing collection of stuff that people accumulate and to empathise with a man who would be left with nothing in two weeks. In fact, James reports, from the intended exploration of materialism the project evolved into an experiment in personal identity – who are we when we begin again, stripped of all the possessions that reflect and cocoon us? We are still whoever we were, is the conclusion – Landy remains the same person, and no unhappier for the experience.

A full programme for the year 2002 began in February with film-maker Atom Egoyan's evocative meditation on memory and the past, Steenbecket, in the dark disused rooms of the Museum of Mankind, and will continue with an installation two miles below the ground, a project in the lost village of Imber on Salisbury Plain, and other amazing events. To find out about Artangel's current programme, phone 020 7713 1400 or look at the website To become an angel, contact Natalie Kancheli at Artangel or e-mail [email][/email] Why should I give money to such frivolity, I hear some readers ask, when there are starving people in the world? Well, there's no imperative to, and we must all choose for ourselves what to do with our spare cash, but there is much to be said for the role of art in the lives of humanists, and for what it does to raise the spirits and enrich one's consciousness. It has to be paid for somehow and, for those of us who will never be artists, paying for it is one way of becoming involved in the creative process.