As the promotional bandwagon behind the hit musical, Les Miserables, begins to roll, a year ahead of the show's second Irish run, the man with the musical touch was in Dublin to oversee events.

Sir Cameron Mackintosh, with Scottish roots and a name to show it, is the producer of Les Miserables and his CV appears to list a connection with most of the major musicals of the past 20 years: Oliver, Cats, The Phantom of the Opera and Miss Saigon.

Sir Cameron got his Christian name from his father's best friend, a cousin killed in the second World War, but it has been pointed out to him that it is also an anagram for romance. He denies, however, that this has "any significance" although it is a theme that runs through his most successful productions.

He is careful about being tagged with a creativity label. "I am not a writer. I am good at construction, and I come up with good ideas. But I need someone to create something for me to put my own input into it," he says.

A multimillionaire, with one estimate valuing his personal fortune at £300 million (he corrects me when I say dollars), he says he has no idea of what his business is worth. "Who can really put a value on what the subsidiary rights of Les Miserable are in the future?," he asks.

He denies being a businessman, but refers instead to the skill of never overspending on his shows. "I will not spend it needlessly and I treat spending that money like running a house."

He attributes that skill to his mother who was "very, very careful" around the home. "My mother is Maltese and she had survived the Great Siege of Malta for four years, and they ate rats and cats and everything they could get their hands on."

Although Les Mis appears to be an extravagant show, the £2.6 million cost of the current touring production compares favourably with a West End musical which, he says, costs £4 million on average. "Les Mis is still a reasonably produced large musical and it has done incredibly well. The London production has made over £21 million profits just in the Palace production.

"I am very practical about the money and I am very lucky to have made money out of it. Very few people make money out of the theatre and hardly anyone has been as lucky as I have to have had as many hits which have gone on to be such worldwide successes."

Sir Cameron maintains that being careful with a production is not the same as being frugal. He points to the example of the big-budget film, Titantic which this week overtook Forrest Gump as the fourth top-grossing film of all time. "How many people were burying Titantic six months ago, all rubbing their hands saying that it was another Waterworld, but under the water?," he asks.

Les Miserables played in its original version in Paris in 1980, but it was not until Sir Cameron acquired the British rights and introduced a new version in the Barbican with the Royal Shakespeare Company in London five years later that it began to succeed.

Sir Cameron had already made his name with Cats. His company and investors put up £600,000 - two thirds of the cost - to transfer the show to the West End.

When staging Cats with Andrew Lloyd Webber in 1980 he sought a minimum stake of £750 each from a group of investors and, since then that "kernel" of about 200 people has remained with him, investing an average of between £2,500 and £5,000. Once a show has recouped its capital costs, profits are split 40:60 between the producer and the investors.

Mackintosh has seen the imminent "demise" of the musical predicted many times but he says the explosion in home entertainment will never be a substitute for the theatre.

"You cannot cram a musical into the corner of your living room.

"When it is in full flight, there is nothing more exhilarating than a musical."

One blemish on his record is Moby Dick, "one of those shows which is completely mad and has some great poppy music to it". It flopped after being transferred to the West End. But he does not let go of the idea that it could be a success, saying it needs a niche venue. "It was such a fringe idea that stuck in a 1,000-seat West End theatre, you could not accept it for what it was."

He remembers going to Salad Days as an eight-year-old, a show which featured a magic piano that made the whole of London dance. It was the experience of seeing the reality behind the illusion when backstage afterwards that started him on his career path 31 years ago.

He began as a stagehand at the age of 18, working on Camelot at the Drury Lane Theatre, and has done most stage jobs - a useful experience for his current position.

Sir Cameron has had his bleak moments, remembering Anything Goes, after it took two years to come to stage and "closing it after months and months of struggle". He was told that if he survived that, he would survive in theatre.

Les Miserables has been seen by more than five million people on Broadway alone, grossing in excess of $240 million (£170 million). Worldwide, more than 40 million people have seen it in its 13 years of life, and it makes about £20 million a year in pretax profits for Cameron Mackintosh Ltd.

Sir Cameron says that he has now read the Victor Hugo novel, although he had not when he first produced it. But he remembers the opening night at the Barbican when he cried for half an hour.

"Somehow I could see that something extraordinary was happening in the theatre.

"It was more beautiful and moving than anything I could have imagined."