A FEW months ago, a colleague phoned to report a sighting in Los Angeles of John Mauceri, a former music director of Scottish Opera. Some time later, in a wholly unrelated conversation, a group of people asked the question: whatever happened to John Mauceri?

Then, two weeks ago, I was browsing through this month's issue of the BBC Music magazine, and, deep within a lengthy essay by Humphrey Burton, one of Leonard Bernstein's biographers, came across a passing but highly significant reference to John Mauceri.

As to what happened to Mauceri, more of that later, but the unconscious link between these disparate references to the American conductor is the 50th anniversary of Leonard Bernstein's Candide, an operetta, light opera, musical, masterpiece, hybrid, mess or farrago of nonsense, depending on your view.

Bernstein had immense trouble with the creation of his Voltairean tale. It was conceived for Broadway, though with a more serious, "arty" tone than perhaps Broadway tastes might have expected. Lillian Hellman, who wrote the book for the opera, went through hell and, according to Bernstein's biographer, 14 drafts in an attempt to get it right.

It bombed on Broadway, where, arguably, it should never have been staged. Numerous attempts to get it right failed to get off the ground, or even off the page. Bernstein returned to the score repeatedly over the years, rescoring, restructuring, rewriting, re-thinking.

It haunted him for 30 years. The overture, meanwhile, passed into the concert hall repertoire, a perennial favourite in symphony orchestra programming, from the most heavyweight concerts to populist, Raymond Gubbaytype events.

There were those, however, who believed absolutely in the work as an entity. One of these was John Mauceri, a Bernstein disciple and collaborator, whose own superb recording of Candide with New York City Opera stands as a proud advocate for the piece. He believed not only in the integrity of the composition, but that its true place in the repertoire, where it would ultimately find its due success, was in the opera house and not on the west end or Broadway stage.

Why it has taken nearly half a lifetime to arrive at what seems like an obvious solution is something that, clearly, haunted the late, great Lenny himself. The reason it seems so obvious lies within the score. The most superficial analysis of the music suggests that it needs operatic voices and not voices, however well-equipped (and however well-miked) on the stage of the musical theatre.

During John Mauceri's seven-year tenure as music director of Scottish Opera, the dream of composer and conductor came to fruition. With Bernstein's approval, Mauceri prepared from the original material a workable final performing version of Candide for production by Scottish Opera. Jonathan Miller and John Wells were brought in to work on the book.

The experience, for all of us who moved within its orbit, and loved the piece anyway - many did not, and some hated it - was memorable, not least for the fact that it brought Bernstein himself to Glasgow in 1988.

Now there was a moment for the memory books. Bernstein arrived at the Theatre Royal during an afternoon rehearsal. The auditorium was dark, populated by production and music staff (and the odd infiltrator). The Orchestra of Scottish Opera, with Mauceri in overdrive, was at full pelt.

Suddenly, the door of the side entrance to the stalls swung open and in swept Lenny, camel coat draped over his shoulders, instantly bopping and grooving to the music. The aura around the man was almost tangible.

Later, I found myself almost tongue-tied as Mauceri introduced me, and Bernstein, talking ten to the dozen, sprayed my face equally with bits of sandwich and cigarette smoke while raving about the work of Mauceri and the Scottish Opera team. That he approved of his disciple's work was confirmed when Bernstein conducted it himself in a CD recording.

As for Mauceri, his fortunes with Scottish Opera were mixed. There were, ultimately, management problems. He had his detractors, including those who simply did not feel he was the right man or the right type of musician to take on Sir Alexander Gibson's mantle at Scottish Opera. Some, I suspect, did not think him a serious opera man at all, though that probably says more about them and their prejudices rather than about John Mauceri.

I got on well with him, by and large, and found him a genial and warm man (perhaps with an edge) whose musicianship was underrated - his Gershwin performance in Girl Crazy was impressive, and his conducting on Ute Lemper's legendary Decca CD of songs by Kurt Weill, with Mauceri evoking the very reek of Berlin cabaret in the accompaniments, is a truly great performance.

BYTHE time Mauceri quit Glasgow in 1993, I suspect he was glad to get out of the company. He didn't need the hassle. He was going to a very nice, lucrative job running the Hollywood Bowl Orchestra in Los Angeles.

He did witness the early days of the attempted merger of his Scottish Opera orchestra with the BBC SSO. He kept his own counsel until he was leaving, when he finally gave his opinion: "The Scottish Opera Orchestra is the one part of the company that really works. Why screw around with that?" Then he was gone.

For those who have inquired, Mauceri recently concluded his successful 15-year tenure with the Hollywood Bowl Orchestra. In late September, a huge valedictory concert, running two nights at the Bowl, was staged to mark his farewell to Hollywood. Now 61, he has moved on to become chancellor of North Carolina School of the Arts.

In that concert, with audiences of 20,000 per night, Mauceri's programme, as well as new music by composers as diverse as Danny Elfman and Richard Rodney Bennett, also included a performance of Glitter and be Gay from Candide. I wonder if the events of 1988 in Glasgow's Theatre Royal flitted through his mind at all?

The work on Candide goes on. As part of a New Year celebration of Leonard Bernstein, BBC4 will televise a 50th anniversary performance of Robert Carsen's production of the opera from the Theatre du Chatelet in Paris. (Scheduled for Hogmanay at 7pm, but check listings. )