IT was always likely to be a tall order. Persuading the personally reticent - and more than 6ft of - Giles Havergal to reflect over his time as artistic director of Glasgow's Citizens' Theatre. Less like turning an oil tanker than deflecting the Roadrunner from his path. It never happened in the cartoons, and it ain't likely in a quiet office in the Gorbals.

The facts are that the patrician face of the Citz will clear his desk on or around his 65th birthday at the beginning of June. He will leave a building that has, since the late 1980s, been completely transformed under his leadership. He will also leave a concept (the Glasgow Citizens') that has worldwide currency as a brand of quality theatre. Whatever the Scottish history of that brand - in the founding of the company by playwright James Bridie and his circle a quarter of a century earlier - it has been Havergal, together with director/designer Philp Prowse, and dramaturg, actor, and director Robert David MacDonald, who made that reputation.

Havergal was appointed in 1969, replacing the man who had beaten him to the post a year earlier, Bob Cartland, and the Citizens' was in

a mess. Successive directors had departed after conflicts with a conservative board. Havergal, a man equal parts diplomat and iconoclast, made an ally in new board chairman Bill Taylor, which was just as well when all hell broke loose for the new regime's first Shakespeare. This Hamlet, with an all-male cast, some sparsely clothed, and a radical version of the text, incensed the critics and pulled in the punters in droves. It was followed by many other equally attention-grabbing productions, accompanied by a cut-price ticketing policy that ensured the merely curious were not put off attending.

It would be uncharacteristic for Havergal to want to discuss any of this. It's in the past, he will say, with an extravagantly dismissive wave of a long arm. He would rather give The Herald an exclusive preview of the theatre's diamond jubilee season this autumn than talk about old times.

It will open with the return of actor Greg Hicks in a Philip Prowse staging of Thomas Otway's Venice Preserv'd. It will also include a production of Brecht's The Resistible Rise of Arturo Ui, famously staged at the Citz by Michael Blakemore with Leonard Rossiter. The pantomime will be a new Snow White, directed by Kenny Miller; Jon Pope is adapting Jean Rhys's book about the first Mrs Rochester, Wide Saragasso Sea, and Tam Dean Burn has an adaptation of Louise Welsh's novel, The Cutting Room.

''I'm anxious not to be too retrospective or valedictory,'' explains Havergal, unnecessarily. ''Philip is still there, Kenny is still there, Jon Pope, and so on. Gradually that will change as new people come on board. Theatre doesn't end, it merely changes. I think that's a much better way of looking at it than, 'I did it my way'.''

Havergal gives one of his big, expansive laughs. ''This autumn season is a kind of bridge. It is a continuation of what we've always been doing, only two people have stepped off the bus - although David MacDonald may be involved in a translation in the autumn season.''

It is unlikely, then, that Havergal foresees the sort of sea-change that came in the wake of his arrival. Perhaps there is now nothing new under the sun. The most recent theatrical outrage has been the appearance in London of Barcelona's La Fura dels Baus with the Marquis de Sade's The Philosophy of the Boudoir. Prowse directed it at the Citz in 1982.

Havergal recalls: ''Someone from the university said that it was so vile it would be impossible to stage. They were quoted in the Evening Times and we didn't have an empty seat. But being shocking was never the point. It sounds naive but it never crossed our mind. The scale of the reaction always came as a surprise. The early days were exciting to live through, but then we've had a lot of nearly skidding into the bus stop down the years.

''It did make it quite exciting but I don't think any of us were interested in the notoriety. What was interesting was that theatre became something that was significant and important, and people cared enough to complain about it or enough to come and see it.''

Which is what Havergal still strives for now, of course.

''We've always tried to disregard the heritage: that is something for people from outside to talk about. Inside, all we're trying to do is get a playlist together and run a theatre, and get people in to see the shows. I don't have any idea of being here 33 years, because we've always been pushing on and not looking back.''

For him, though, the stage and the auditorium are sacrosanct and the origin of the special relationship between those on stage and the audience. Nonetheless, the seating, the flooring of the stage, and the counterweight system that moves the scenery are all new in the Havergal era.

If he is unhappy being remembered as an enfant terrible, he is none too keen on being an elder statesman, either. He reluctantly accepts it, however, as a consequence of the role he has played within the Federation of Scottish Theatre. It has secured funding for Scottish theatres on a par with that introduced in England after the Boyden report, and joined in the debate about the founding of a Scottish national theatre. ''I think the federation has fought a

really good battle on every front. If that has given me Old Man of

the Sea or Prophet Elijah status, I'm not bothered.''

That position has also been earned by the future careers of people who have worked for Havergal, and actors who choose to return to the Citz, like Hicks. People like Trish Biggar, now creating costumes for the Star Wars films; and Neil Murray, running the Tron. Actors like Rupert Everett, Gary Oldham, Maria Aitken, Shirley Henderson, Dougie Henshall, Glenda Jackson, and Pierce Brosnan. The fact that directors of the education arm he and Taylor fought to save in the 1970s (TAG, now an entirely independent company under the same board) went on to run the Traverse, Lyceum, West Yorkshire Playhouse, and now Dundee Rep. ''It rather pissed me off when it suddenly became all the rage to talk about access and inclusion. What else had we been doing? All those years ago it was an inspiration of Philip's to have all seats at 50p; the free preview, which was an idea of David's; and then they say there

will be extra money if you do this. Well, we'd been doing it for years so we didn't get the extra money.

''It isn't like there's the work and there's education. There's no point in popularising the work to get people in. You've got be offering the highest standards you can.''

If those robust, if always diplomatically expressed, opinions are missed in Scottish theatre, so will be the towering presence of Havergal in the foyer of the Citizens'. Throughout his tenure, Havergal was often to be found there, greeting theatregoers. It was the way he was trained, he says, under an ABC television scheme which saw him apprenticed to Carl Paulsen at Oldham Coliseum.

''So far, no-one has come up and punched me on the nose, but I always felt that if they were furious they had that option.'' (If they were furious and possessed of a very long reach, it has to be said.)

Havergal leaves with the prospect of some film work in Portsmouth over the summer; a continuing relationship with the American Conservatory Theater of San Francisco that will see him directing his own adaptation of Les Liaisons Dangereuses in September; a BBC Radio 3 commission to adapt Joyce's Ulysses for its centenary next year; and the prospect of more performances of his hugely successful one-man staging of Thomas Mann's Death in Venice.

''It will be nice to be asked to do anything,'' he says, ''but I will miss the business of not being part of an organisation for the first time in 40 years, because I ran my first theatre when I was 26. Of course, this happens to masses of people who work in organisations, in local government, or in banks or schools. There comes a moment when they aren't there any more and I shall just have to deal with that.

''I'll miss the people and I'll miss the building, but I've had it as a sand-pit for 33 years, so it's time someone else had it.''

Hamlet (1970)

Havergal is grateful no video exists of this legendary production, with David Hayman playing the prince as, according to one critic, ''a gibbering oaf''. His version included graphic depiction of Hamlet's mother and Claudius.

The Last Days of Mankind (1983)

One of Robert David MacDonald's adaptations of allegedly unstageable texts, following his summarising of Proust as the ironically titled A Waste of Time two years earlier. For four hours Havergal sat at a cafe table as the writer Karl Kraus, and became known as Giles the Piles. A radio version of the text was directed by Havergal for the millennium.

Travels with my Aunt (1989)

Following a budget-busting production of Macbeth, the theatre was left with no money to complete the season. Havergal created this version of Graham Greene's novel for four men in grey suits and V-neck sweaters. Cheap and cheerful it may have been, but it has been revived often, including a San Francisco run directed by Havergal in 1997.

Death in Venice (1999)

The Herald's critic said it was a privilege to be one of the few who saw this one-man performance of Thomas Mann's novel, during its stalls studio run. Havergal, right, has since performed it all over the world, picking up a critics' award on Broadway along the way.

Scrooge (2002)

Citizens' Christmas shows were for a long time Havergal's preserve, beginning with an Aladdin in 1971, written by Terry Jones and Michael Palin. That story-telling skill has been passed on to designer director Kenny Miller, who gave Havergal, far left, the perfect role for his swansong: A Christmas Carol.

Havergal's greatest hits