This attitude is almost holy writ among theatre people who worship of the feet of Paris-based director Peter Brook, who champions the physicality and immediacy of the actor-audience relationship. Although when asked to name his favourite playhouse, Tompkins does not name Brook's Bouffe du Nord theatre, as most do. Instead, he cites the Cartoucherie, an old ammunition factory also in Paris, where several companies including Ariane Mnouchkine's Theatre du Soleil exist. "Everything about it is all wrong, but it works," is Tompkins' conclusion. "There are theatre groups now who deliberately don't perform in an auditorium. That's the paradox. The idea of seats facing a stage may not be a meaningful idea. We may be getting to the point where the auditorium is irrelevant."

Not that there's anything new in the use of found space. The modern theatre, as he points out, evolved from galleried Jacobean inn-courtyards and their continental equivalents. And besides, he's never done an all-new theatre, he's always had to deal with "stubborn, problematic" old buildings. Thus at the Young Vic, which famously incorporates an old butcher's shop, much of the old will remain. "We're working a new layer of possibility into it, making a hybrid of old and new," as he puts it. It's a similar task for Egg in Bath.

For whatever reason it's other architects who get to do the few all-new theatres around at the moment (see panel). These inevitably enshrine a particular set of current ideas about the theatre. Tompkins would love to do a complete theatre from scratch, no doubt about it, but so far his exercises in creative remodeling seem to have hit the mood of a certain cadre of "found space" actors and directors. Not for him the world of cosy permanence, let alone West End musicals.

"There will always be a place for the extravaganza. But it's not a world I'm familiar with and I haven't worked in it. The Royal Court, the Young Vic, the Almeida - their roots are in a more radical tradition, albeit not as extreme as performance art."