If Sir Trevor Nunn has a fault, it is that he tends to go on. And sometimes on and on. He has dazed diners with his speeches when accepting awards. When we were fellow students at Cambridge in 1962, I recall giving him possibly his first bad review for a relentlessly slow production of Macbeth. And one problem with his musical Gone with the Wind, which has opened to mixed reviews at the New London, is that, at 190 minutes, it is too long.

Yet some of his greatest successes haven't exactly been short. In 1985 he staged (with John Caird) the musical verson of Les Misérables, and it's still running in the West End. Almost more famously, he directed the RSC in Dickens's Nicholas Nickleby in 1980, inventing a method of narrative (individual actors becoming a serial chorus describing their own or others' thoughts and actions) that added pace, clarity and completeness to a two-part production. At the time he said that he feared he was leading his cast “over a cliff” - but the cliff was actually an Everest of theatrical attainment.

That self-doubt is characteristic. At 68, Nunn has every reason for confidence but is surprisingly insecure. Maybe that's because there was no silver spoon in the environs of his cradle. Like his mentor, Peter Hall, Nunn comes from humble East Anglian origins, in his case Ipswich, where his father was a joiner. But, also like Hall, he had the ability to dominate Cambridge's undergraduate theatre.

He has not looked back. After a stint at the Belgrade Theatre in Coventry, he joined Hall's Royal Shakespeare Company and succeeded him as its artistic director at the age of 28. It was an inspired appointment, for the RSC has never been stronger than it was in the 1970s.

His stint as the National Theatre's supremo from 1997 to 2003 was more controversial - he was accused of pandering to middlebrow tastes, especially with his revivals of musicals. But as these included his own superlative staging of such classics as Oklahoma! and, among other new plays, the world premiere of Stoppard's Coast of Utopia, the objections seemed snobbish or misconceived. On leaving the post he answered the tattle that he was profiting from West End transfers by presenting the theatre with a gift of £2.5million.

He is principled, wealthy, married to the actress Imogen Stubbs and, all cavils aside, a brilliant director. Nobody can handle a large stage, and few a small one, more effectively than Nunn. His recent Lear, with Ian McKellen, was a triumph, yet McKellen has never been better than he was in Nunn's pocket revival of Macbeth in 1975. Furthermore, his revival of The Merchant of Venice in 2002 was surely the best of that difficult play. Whatever the prospects for Gone with the Wind, the Nunn's tale is not yet finished.

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