CORRECT me if I'm wrong, but it seems to me that it is unusual for a rising young international conductor of considerable repute, who is also the music director of a well known, well-funded and well-thought-of international orchestra, to come to Ireland to conduct as well, let's face it, a smallish and newish orchestra.

But as its magazine, ICO Bulletin, demonstrates, the 16-member Irish Chamber Orchestra is a small orchestra with appealingly big ideas; and the American conductor Kent Nagano is nothing if not a master of the unusual. In 1990 he took an obscure Prokofiev opera, recorded it with Opera de Lyons - and suddenly everybody was talking about The Love For Three Oranges, which went on to win a Gramophone record of the year award and was nominated for a Grammy. That was his first operatic recording. His first appearance on the international podium had been even more spectacular; in December 1984, at 24 hours' notice, he conducted the Boston Symphony Orchestra in a performance of Mahler's monumental Ninth Symphony without rehearsals and never having previously conducted the work.

Since then he has accelerated into the conducting big-time premieres of Olivier Messiaen's Transfiguration and St Francois d'Assise, premieres of John Adams's opera The Death of Klinghoffer in Brussels, Lyon, Vienna and the US, Stravinsky's Oedipus Rex at Salzburg in a production by Peter Sellars. He is music director of the Halle Orchestra in Manchester and the Berkeley Symphony Orchestra in California. So how come he is to be found, this weekend, conducting the Irish Chamber Orchestra in two concerts of Stravinsky, Mendelssohn, Mozart and Britten?

The answer lies in his tenure of a guest conductorship at the London Symphony Orchestra in the early 1990s. One of the musicians who greatly impressed him there was a young Irish violinist by the name of Fionnuala Hunt. "We did several concerts and a recording together, and I really enjoyed working with her," he says. "To the point where at one stage, when I was missing both of my concert masters in Lyon, France, I asked Fionnuala if she would fill in the vacancy and tour with us so on the US tour of the Opera de Lyons, Fionnuala was one of our concert masters, and a soloist, too. She's fantastic. I enjoy making music with her a lot."

So when Fionnuala Hunt - now leader and artistic director of the Limerick-based Irish Chamber Orchestra - asked Nagano to do some work with her ensemble for a change, he was happy to oblige. The potential gains for the ICO are obvious, as Hunt points out in the orchestra's magazine: "It opens doors for working with many other conductors. And next thing, agents are suddenly phoning me and offering all kinds of conductors and performers". But what's in it for Kent Nagano? Are there particular pleasures to be had from conducting a chamber ensemble as opposed to a full-sized symphony orchestra or is it just the same thing on a smaller scale?

"I suppose in its most general terms music-making is music-making, no matter what level you make it on, be it as a soloist or in chamber music, or a chamber orchestra or a symphony orchestra," he says. "But of course working with a chamber ensemble does shave a whole different set of dynamics to working with a very, very large ensemble, because of the nature of having less instruments, and as people are exposed in a more soloistic way.

"I need to be really careful when I say it's more or less or better or worse, because these words are really inappropriate when you're talking about sharing a musical commitment - but it is different, I think, and certainly a performance by a chamber orchestra can be just as dramatic and just as intense as one by a large orchestra. But the nature of each person's role, within that smaller ensemble, is quite different."

"Careful" is the word. In conversation by phone from San Francisco, where he has just moved into a new house which workmen seem to be doing their darndest to demolish by means of insistent demonic drilling, Nagano gives careful, thoughtful answers punctuated by occasional ripples of laughter. This is a man who is deadly serious about music - but not, one suspects, deadly serious. A man of surprises, undoubtedly, and less austere than the intimidatingly chic photographs which invariably accompany his opera recordings might suggest.

But will it surprise those who know Kent Nagano from that eclectic collection of recordings - Poulenc Busoni, Stravinsky, Carlisle Floyd - to find him conducting Mozart and Mendelssohn? "Well, maybe, unless you've come to the Halle, he says with one of those ripples of laughter. But it's true, most of my recordings have been with Opera de Lyons, and there we've tended to go for a very, very adventurous repertoire - to expand the limits of what would normally be regarded as an operatic experience, and try to make it more pointed or oriented toward the future. We didn't want to be just another opera company; we wanted to be `Lyon Opera'. So we really searched for our own personality and our own character.

At the Halle, on the other hand, he found a longstanding tradition already in place - which, for a young whippersnapper with no shortage of unusual ideas, represents a challenge of a different kind. "Yes, it's a very long and proud tradition which one can have the privilege and pleasure to be a part of - and I really mean that, because there aren't that many orchestras which share that depth of tradition. Of course it's not without its own set of problems, and we've had a lively exchange of ideas in terms of what exactly `tradition' means. And we're not alone. If one looks at all the discussions that have taken place around, for example, the Salzburg Festival and its new direction, those discussions were very interesting. We always felt at Lyon, and now we're starting to feel at the Halle, that discussion is debate - and that debate can be a prime indicator of the fact that a tradition is a living thing and can continue in a creative way."

Tradition notwithstanding, Nagano's name has become synonymous with the presentation of 20th-century and contemporary music. Clearly he believes it is important for audiences to listen to the music that is being written now, but how does he, persuade them to listen? Aren't people reluctant to commit themselves to something they feel is going to be different, not to mention difficult? "I think," says Kent Nagano, "it can be taken as a given that we human beings - and I include myself in this - tend to be less comfortable with things that are _ brand new or unknown than with things that are well known and loved. It's human nature, I think, and it goes right through human nature it doesn't matter what country you're in or what city you're in so if one is going to share something that's unusual or unfamiliar one needs to be very, very careful to make sure that the choice of that work can be backed up by meticulous scholastic discrimination.

"That still leaves open to debate whether an audience member or an orchestra member likes the piece or not - but not everyone's going to like everything anyway, and that goes for standard repertoire as well. But at least one should be able to say confidently that there is a specific reason why the piece was heard, that you can provide arguments as to why the work was an important piece to hear.

"Very often, both in Lyon and in Manchester, people ask - but why did you feel the need to perform that piece?" He chuckles at the memory of it. This is not a man to quail if attacked by a belligerent public. On the contrary, he says he enjoys the chance to provide explanations. "It's important that people ask `why?'. And sometimes the reason has been as simple as respect for the community in which we live. If a work by a certain composer is considered great by most of the big international centres of the world, then it's really, really important that people who come to our concerts have the opportunity to be exposed to that repertoire and make the judgment themselves, whether it's a great piece or not. I think the worst case is when one forms an opinion based upon ignorance or on second-hand information or third-hand information - or just on gossip."

THE business of making judgments becomes particularly thorny in the field of opera where, though the latest statistics from the US suggest that opera as a whole is more popular than ever before, premieres of new works are rare events indeed. In his recently-published book, Believing In Opera, the distinguished critic Tom Sutcliffe suggested that if the form is to survive into the 21st century, opera composers will have to come up with a few good tunes. Does Nagano agree that the lack of melody is a major stumbling-block? "Well, melody can be quite subjective in terms of whether or not it's tuneful," he says. "When one performs, for example, Messiaen's Turangalila Symphony, it's surprising how many people leave the hall humming one of the great melodies from that work - so there is a bit of subjectivity, perhaps a bit of prejudice, that goes into whether one can call a work tuneful or

The programme he will conduct in Limerick tomorrow night and in Dublin on Sunday can hardly be accused of stinting on melody, featuring as it does the Mendelssohn Violin Concerto with Fionnuala Hunt as soloist, and Mozart's Piano Concerto in KS 37, with Nagano's wife, the Japanese pianist Mari Kodama, as soloist. The concert opens with Stravinsky's Concerto in D and closes with Britten's Variations on a theme of Frank Bridge. "Well, you know," says Kent Nagano, "I showed this programme to some of my friends here in the US, and they said `oh, my, what a contemporary programme...'

"I guess that's what I mean about perspective. Here in San Francisco last year I did a rare performance of Elgar's Enigma Variations, which was considered very unusual, very contemporary and highly provocative programming." This time he positively chortles with delight.