Michael Colgan: What I have discovered is that there is a sense in which we have to look at our imaginations and see what is being changed. Two imaginations have to be in line with each other, the giving imagination, which is the imagination of the writers, actors and directors, and the receiving imagination of the audience and critics, because there might be a piece of greatness that comes along and is ignored. Mark Twain said, "it doesn't matter what you see if your imagination is out of focus".

There is never going to be a failure of the imagination among artists; they are always going to produce something, and people like me have got to have the imagination to be ready to see what's happening.

For me, the most fundamental change in the last 10 years, more than anything else that was said to be a threat to the theatre, is the change in the imagination. It is the most potent force in the arts today.

For instance, I recently went to see L.A. Confidential with my 16-year-old daughter and my mother. It starts with cross-cutting, cameras flashing, simultaneous sounds, half-sentences, over-lapping dialogue, American slang, characters talking in unison, everything topping everything. I was giving it my best just to hold on to it, not helped by my mother who was giving it her complete best but was hopelessly lost, and my daughter said, "What's wrong?" I said, "Nana doesn't understand it," and Sophie said, "Doesn't understand what?"

She had time to talk to us and she understood every single thing that was going on. The speed, the density was perfect for her. Her world is an entirely different world from ours. It's not a failure of the imagination to say it would be easier for my mother to sit through three and a half hours of King Lear than it would be for my daughter. Mv daughter would be bored. Maybe the failure is mine in not recognising that, like technology, or maybe because of technology, our imaginations are also rapidly changing.

Jeananne Crowley: So the parameters for receiving have changed?

MC: Completely. And that's why it's no accident that our new movies are on MTV. Our new movies are ads.

JC: Where does that leave the theatre we love?

MC: The theatre you and I love is going to have to adjust to that, because if you are a giver in the shape of a David Mamet, say, or a Harold Pinter, you are also a receiver. You also go and see things. In other words, you yourself are subject to this change. If you look at the work of Mamet and Pinter, they're not writing two and a half hour plays any more, nor indeed was the genius who understood this turn before any of us did. Sam Beckett could write a play that was 22 minutes long because an audience need was not on his agenda. Pinter and Beckett both had a route into their own subconscious, and they could do what they needed to do.

It's not that they didn't care and were putting two fingers up to the audience, I don't believe that for a second; it's just that they weren't writing for an audience. What worries me is that so many playwrights who are "artists" - and many of them are - all happen to write plays that are two hours and 15 minutes long with a 15-minute interval and usually with one set if they can do it, because it's very producer-friendly, and on top of that maybe a cast of eight that's manageable, and give it a sexy title. Well, there's nothing sexy about a play called Act Without Words 2 that is 22 minutes long. It's not exactly producer-friendly, but Beckett, who had a route into his own subconscious, could go in and do what he felt was right.

It wasn't that he didn't care about the audience . . . it's that they weren't on his agenda, he wasn't writing for them. And now we are all experiencing this shift. The ads on telly 10 or 15 years ago would be intolerable now. Ads are now 30 seconds, and they are a complete story with a beginning, middle and end. They are funny, clever, witty, and there is characterisation - look at MTV. I think it's one of the most extraordinary art forms. I watch MTV all the time.

JC: There are very few Becketts in the world. Are you saying theatre is going to have to accept and understand a new form? Can it not survive as it is, demanding in a way, or at least asking its audience to sit there for two hours?

MC: I don't think audiences will sit down for two hours anymore unless you give them a reward. And the reward you give them is by telling them that they have been to an Event. When you Event something, you've a much better chance of getting them to sit through even five hours.

They can get together, make it a communal event, have supper and sandwiches, and they're all happy doing the marathon. I had no difficulty in getting people to come and see the Becketts in 1991 in London and in New York.

Similarly, the Event in this year's Dublin Theatre Festival was the Tom Murphy plays because they were Evented. And we will continue to event with a capital "E". When you event with a small "e", you really do have to make sure you have an Anthony Hopkins doing King Lear, so you event in a different way. In other words you don't do Lear with an ordinary cast; and if you do, you depend on the schools. That's the tragedy. So when you ask if there's a new form, of course there is. It's changing as we speak. Theatre is getting shorter. I've had arguments with people who feel that our imaginations are in some way failing and we can't sustain it; that we don't have that sort of strength of the imagination anymore. But I disagree with that entirely. I think we have new imaginations, different imaginations.

Theatre Talk: Voices of Irish Theatre Practitioners, edited by Lillian Chambers, Ger FitzGibbon and Eamonn Jordan, is published today by Carysfort Press