It's always dangerous to start parcelling theatre up into different and possibly conflicting categories: musical theatre, new plays, classical revivals, site-specific performance, and so on.

Good theatre is good theatre wherever, and however, it happens. And a solo Beckett programme is as much performance art as Frantic Assembly, or Tim Supple's six-hour staging of One Thousand and One Nights.

But David Edgar is surely right to argue, as he does in the current issue of the New Statesman, that the contemporary writer is what makes the British theatre really tick, flying flat in the face of an Arts Council policy document of ten years ago which argued that text-based drama -- everything from Aeschylus to Ayckbourn -- was in terminal decline.

I've always been sympathetic to the view that the most important ingredient in the theatre is not the writer, or the director, or even the actor -- but the audience.

We are in the fortunate position of being able ot take our actors for granted. Not a week, not a day, goes by without some astonishing new performer emerging, and the quality and brilliance of our actors from the Gate in Notting Hill to the Lyttelton on the South Bank is never in question, except among cantankerous critics like me.

But what really distinguishes our theatre from the rest of Europe, and the rest of the world, is its writers. I like Edgar's submission that the "current outbreak of Rattigania" is a bit excessive; his best, and best known, work has never gone away. And just look at the recent resounding revivals of Arnold Wesker, "the emblematic kitchen sink writer."

Even the divide between performance and text-based theatre is now being breached, says Edgar, by playwrights such as Abi Morgan, Bryony Lavery and -- most significantly, perhaps -- David Greig. I've always felt that the core of what is best about Tim Etchells' doggedly "physical" Forced Entertainment are the textual leaping off points, anyway.

And look at this week in the London theatre, one of the most exciting in the calendar since -- well, probably last week, and very likely next week, too.

On Monday, the opening of The Wild Bride at the Lyric, Hammersmith, was widely acclaimed as a return to top form by Kneehigh, and the script of Carl Grose is not an inconsiderable part of its overall theatrical impact; it also contains one of the funniest lines I've heard in a theatre for ages, when the heroine's impoverished father is compelled to sell his own daughter to the devil and exclaims: "I'm so poor I can't even pay attention."

Then, at Hampstead Theatre last night, Steve Thompson's No Naughty Bits was avowedly about the court case the Monty Python team initiated against their American broadcasters for eviscerating their saucy passages; but in fact it was a cunningly wrought comedy about language and the meaning of laughter.

Tonight, the Tricycle in Kilburn is hosting a new play, The Absence of Women, by the brilliant Irish dramatist Owen McCafferty. Tomorrow, Stephen Poliakoff returns to the theatre at the Almeida with My City, his first stage piece for over ten years. And on Friday, Antony Sher and Tara Fitzgerald open at the Vaudeville in Arthur Miller's Broken Glass, one of the better of his later plays.

There is no city in the world that offers such riches of contemporary playwriting; Dublin and Edinburgh run London close occasionally, but not consistently, in this respect. New York, Paris, Berlin? I think not.

So I'd better take a short break and see how new writing, and new theatre, is coming along in Belgrade, where I'm heading this weekend for a few days of the annual BITEF festival. I can't stay too long: I have to be back next week for yet another new play at the National Theatre, Mike Leigh's Grief. Sounds hilarious.

Extraordinary, isn't it, how some folk are always complaining about the fact that there is nothing in the London theatre except musicals. Sometimes I wish they had a point; but, on the whole, they simply don't.