How do you put together a retrospective of a performance artist? The Beckett-inspired 'live artist' Alastair MacLennan tells Aidan Dunne how

How do you mount a retrospective exhibition when the work of the artist in question is, by its nature, ephemeral and site-specific? That was the problem that faced Hugh Mulholland of Belfast's Ormeau Baths Gallery and the artist Alastair MacLennan. Since the Scottish-born MacLennan arrived in Belfast in 1975, he has built an international reputation in the field of performance or live art. A great deal of his work has been made abroad, throughout Europe and the US, and essentially it existed only in its making: there is no end-product.

This is particularly so because MacLennan has resisted the various forms of reification and commodification that have crept into the performance arena. These include the isolation of single, iconic images that come to symbolise a live event, or the fetishising of the props and materials used in performance, as in the case of the renowned Joseph Beuys. The result of their deliberations is an exhibition, Knot Naught: A Retrospective that includes a performative element, a stunningly effective installation (which shouldn't be described but should be experienced), a great deal of documentation and a thoughtful, provocative, illustrated lecture. In other words, a show that is remarkably true to the spirit of the work.

MacLennan, who was born in 1943, is a calm, compact, self-possessed figure, softspoken and polite. Like Beuys, he is partly recognisable through the "uniform" that has become his own. He is usually clad entirely in black and, during performances, often wears a long black coat, hat and dark glasses. He established his reputation for making long - sometimes incredibly long - and intense performances in elaborate settings, with a recurrent range of props, including fish, refectory tables, bowls and earth.

As these references to meals and burial suggest, an element of social ritual runs through all his work. Often the artist comes across as a penitential or even sacrificial figure, an outsider with the responsibility of embodying certain underlying truths about society, of encouraging society to look at itself. The sense of being apart from but inextricably linked to the community is particularly strong, and gives the artist room for manoeuvre, a distance from which to comment. MacLennan has always been acutely conscious of maintaining this balance between independence and responsibility.

He has great presence - and great stage presence - though not in the loud, flamboyant sense that the mere words "performance art" tend to suggest. His is a quiet, self-contained, inward presence. He uses repetitive, ritualistic actions in an almost hypnotic way to generate or augment a meditative, reflective mood.

"Mood, or atmosphere is one of the most important things," he says. "Once you've got that overall feeling you can go on to work within it, explore it, examine it a bit more, and see what other things unfold." His own quietness is important in that respect. "I see it as my job to blend with the overall mood of the thing. That's partly why I'm wary of the term performer. It suggests what you do is the focus, the centre of attention. I try to be more a facilitator, enabling the thing."

Duration is also important, for both artist and audience. "Not just in terms of being long. Duration in the sense of becoming aware of being there second by second by second, so that time becomes palpable. It makes us focus on what it is that we are living through." Even his lecture, peppered with lists of verbs, continually prompts us to think in terms of active involvement rather than passive consumption.

He originally studied painting at Dundee and went on to travel and work a great deal in the United States and Canada.

This included two years spent living in a Zen community on the American west coast. This was, he says, "very difficult, a very strict regime" - but also very useful in terms of both life and work. "I still practise it - it's not a belief thing at all. More to do with trying to be present, to be there."

His father's death brought him back to Scotland. His intention was to go back to Canada. But it had crossed his mind that he had never been to Ireland, and he saw an advertisement for a job at what was then the art department of the Polytechnic and is now Belfast College of Art. He signed on for a three-year stint, intending to head back across the Atlantic after that. But he is still there, more than 25 years later.

"When I arrived here, I found that the art scene was very limited, very conservative. There was nothing for younger artists here. I felt that there was something I could do, that I could make a bit of a difference." He became involved in establishing the Art & Research Exchange, and in the launch of Circa art magazine.

Performance art was unheard of, and he began to make performances or, as he terms them, actuations, unobtrusive, ritualistic actions in public spaces, often to the puzzlement of passers-by, on a weekly basis.

"Students began to show up because they knew I was doing something. And gradually they began doing things as well."

Belfast surprised him in other ways. "One thing that kept me in Belfast - and I know this sounds corny - was something I wasn't prepared for, and that was how the students as human beings were incredibly warm with each other. I hadn't encountered that in America, and that level of caring, a simple thing, helped persuade me to stay. There were also some great artists, like Adrian Hall, around at the time."

There is a hint of Beckett in the show's title and in the titles of various other works. In fact, Beckett is an influence he readily acknowledges. "That goes way back. Some of his stuff is so visually precise that I saw him as a visual artist as much as a writer. And of course the idea of the tramp, the outsider as someone who tells us about our own limitations is important to me."

The visual richness of the photographs and slides documenting performances is perhaps not surprising, but many of the images that form part of the illustrated lecture, depicting the settings of performances, usually aftermaths, are surprisingly beautiful in a bleak, stark way. "I always go around afterwards with a camera. There is this perception that if you do performance you don't do drawings, or painting. In fact I do, and the way I organise a space certainly comes from drawing and painting. They are the backbone, or the ground out of which the performance manifests itself. But I didn't want to show, say, drawings in this context. Maybe separately, on another occasion."

Looking back on the evolution of his work, performance was not an obvious way for him to go. But there were markers. In one particularly illuminating story he recalls, as a student at Dundee, bringing a painting by train to a show in the north of England. It was winter. With other travellers he was awaiting a connection in a small, freezing waiting room.

He was aware of the presence of a tramp, a fairly grubby, bedraggled figure, in one corner of the room. "Cold, isn't it?" the man said to the room in general. "Everybody raised their newspapers in front of their faces and tried to ignore him, to pretend he wasn't there. Then a few minutes later he suddenly said: 'Warm, isn't it?' And it struck me that although he was an outcast, beyond the pale, in those moments he was empowered beyond anyone in the room, he was in charge."

Knot Naught: Alastair MacLennan, A Retrospective is at the Ormeau Baths Gallery until March 1st. Alastair MacLennan is making a series of interventions/actuations in the gallery every Tuesday throughout the run