This Dancing Life, structured on the scale of an opera and described by the New York Times as "a constant interplay of impulses intoxicating and as natural as bird song", is a marathon installation in non-theatrical time during which the audience are free to move around and watch the dancers from different angles. "It's not like something that's going to be playing on the West End or Broadway, " she says. "A lot of it will be done in complete silence. We'll be using a lot of improvisation."

Her regular musicians, William Catanzaro and Jerome Morris, will attune to what's happening physically in the room and provide live accompaniment where required using minor and major scales on piano, accordion, harmonica and a wide range of percussion, evoking world musical sounds like the Balinese gamelan, almost seeming like a country and western song. "Some of the things we are doing are quite gorgeous, wonderful to look at, but we're also doing things to enrich our immediate responses to our environment and to our own self, " she says. "I hope people will give it a chance."

Rudner has been shaking up conventional attitudes to dance since she graduated from Barnard College and formed an experimental all-female company with fellow graduate Twyla Tharp in the basement of a church on Fifty-Seventh Street in New York in 1965. "We were doing wild crazy things, " she says. "We performed without music or sound other than our own breathing and footfalls. We didn't take bows. No one would look at us. We were pariahs."

Their collaboration lasted nearly two decades, during which they changed the nature of modern dance. Rudner's own dance performances include the Milos Forman movies Ragtime, Hair and Amadeus and the lead in The Catherine Wheel, choreographed by Twyla Tharp and directed by David Byrne of Talking Heads. As a choreographer she created Heartbeat for Mikhail Baryshnikov, who with Nureyev is synonymous with dance throughout the world, and became famous for her "occasional dances" based on personal events in her life.

"I come from an immigrant family, " she says. "My grandparents left the Ukraine in the early 1900s during the pogroms and settled in New York.

The patriarch of the family was a travelling musician. He was never around very much. So the lore in my family was never to be in the arts because it's bad for family life.

I was always dancing around as a child, so they gave me some dancing classes until I was 13 in a neighbourhood school. When it closed there was talk of me going to the Performing Arts High School. My mother was not encouraging at all. 'It's not good to be in the arts, ' she said. And I was scared off."

Rudner dutifully went from high school, skipping grades . . . "I was a baby boomer, born at the end of the war, and they pushed as many of us ahead as they could so that there wouldn't be a horrendous backlog" . . . to Barnard College at Columbia University. "I was a distance swimmer as well.

Whenever I was unhappy or needed something I would go into the pool for about three hours. It kept my body mobile, flexible and strong. When I started dancing again . . . the day after I graduated at 20 . . . I was maybe not so aware of my anatomy but I certainly had the reflexes and the strength and the maturity to do what was required. I was one of those naturals.

"Since I was not really in the dance world very much I hardly knew who Merce Cunningham was. I had to be educated. Twyla came from a very different background. She was a very sophisticated dancer. She had performed with Paul Taylor. She had years of training. But there was just something that clicked intellectually and physically between us. We had the same appetite for things."

She got involved in movies through Tharp. "The close correspondence between filmmaking and choreography appealed to us. Every movie involves moving bodies in a space. It's a form of choreography. There's something about films . . .going back and forth and also the editing . . . that I've tried to put into the dancing. It can be inspiring. But dancing on film can be very demanding. You do your warmups . . . you know how it is with dancers . . . and you're ready to go. Three hours later you get to do it."

Heartbeat started out as a 15minute improvised solo she devised for herself in which she attached a heart monitor to her body and danced to its beat. "As my energy got going it could go faster and then I learned what position would slow it down. I usually performed it in galleries on open spaces. When Mikhail Baryshnikov asked if we could work together, I suggested it to him. His version was a lot more theatrical. He did it on a stage which was bare at the start. You could see all the apparatus. As it progressed it became more and more theatrical. At the end he was dancing full-on. It was really very beautiful."

When John Scott, whose Irish Modern Dance Theatre has made a practice of breaking conventions, approached her to bring her work to Ireland, Rudner was initially cautious. "I said I don't know you guys and maybe this work is not for you. I suggested we do a workshop. So we did that two summers in a row and then he just dragged me over.

He's a slave driver. He convinced me to do things. That's how I like working. For me it's like standing at the edge between control and freedom."

'This Dancing Life' will preview at SS Michael & John Hall, Essex Street West, Temple Bar on 12 August. Its world premiere will be in The Carlton Ballroom at Kilkenny Festival on 15 August and it will continue at SS Michael & John Hall on 17-19 August