Acclaimed choreographer William Forsythe is an anomaly in the world of dance. Born and raised in New York, he established his reputation in Germany, first as a dancer with the Stuttgart Ballet and, for the past 20 years, as Ballett Frankfurt's artistic director and choreographer. He has proven remarkably adaptable artistically, creating for his own troupe highly experimental, unballetic modern dances, as well as traditional ballets for major companies such as American Ballet Theatre and the Royal Ballet.

Forsythe's eclectic vision and theatricality have won him considerable renown. Having begun the '90s in relative obscurity, he is now one of our most important choreographers.

"Everyone in ballet is asking -- where do we go now?" says Kevin McKenzie, artistic director of American Ballet Theatre, "and Billy is coming up with answers. He is a groundbreaker. He has taken a system based on Balanchine and provided the dancers with vehicles for improvisation, something ballet dancers are completely unaccustomed to. He asks them to contribute, meaning his pieces look a little different every time they are performed. He removes the boundaries and opens everything up to question."

But when Ballett Frankfurt performs at the Kennedy Center today through Saturday with a program of four dances set to music by a longtime Forsythe collaborator, the Dutch composer Thom Willems, it will be for the last time. In the wake of dispute over the direction of Ballett Frankfurt, the troupe is being disbanded. An engagement in Paris June 30-July 3 will be its last.

Two years ago, the conservative members of Frankfurt's town council, disenchanted with Forsythe's avant-garde style, offered him a new contract that would have provided a fraction of the company's then-current budget of $6 million. They objected to his dances, which appear unstructured and often include spoken text, intense lighting and unmelodic scores. He had also been increasingly staging works in small theaters rather than in the opera house, his hypothetical base, which also troubled the town council.

Rather than accept the offer, Forsythe garnered enough financial support from other government sources in Dresden and Frankfurt to form a smaller troupe with 14 dancers. Called the Forsythe Company, it will perform his more intimate works in theaters in both cities.

"The dances I made for Frankfurt will be performed again, of course," Forsythe said recently, "but under different circumstances. It's both sad and exciting to be leaving -- exciting because I'm entering a whole stage in my career."

He also has just announced plans to establish the Forsythe Foundation, with headquarters in New York and Kirby, Vt., for years his second home, where he will build studios for dance and the visual arts. He will spend eight months in Germany and the remainder of the year in the United States. Through the foundation, he can extend his philanthropic activities as well, first off by sending teachers to Brazil, where he choreographed a work for teenagers last year.

"Now that I won't have a company that is based in an opera house," Forsythe said, "I'll be able to choreograph in more flexible formats. There's an awful lot of movement research that I've never had time for. I want to explore working outside theaters, in smaller, more versatile spaces, and with other kinds of artists. And I'll hold workshops where we can elevate the discourse about dance and find a way to get dance as a subject into schools, so it isn't foreign to so many people."

Forsythe, a tall, easygoing redhead with a ready laugh, said he organized the Kennedy Center program in a practical manner. "I want to reveal the beauty of the inner workings of dance," he said. "Dance is an investigation; it's never a finished thing. I designed the program to focus the audience's attention. The works become progressively more intricate, so people can slowly become accustomed to my way of making dances."

The first piece on the Kennedy Center program, "The Room as It Was," features eight dancers who engage in a series of explosive and lyrical encounters, forming and reforming in duets and trios. They crisscross the stage, swooping, falling and running, only to come to abrupt halts or frantically set off in all directions. As in the next two works, "Duo" and "N.N.N.N.," the audience clearly hears the dancers breathing. Forsythe has determined the times for the dancers to take breaths as assiduously as he has set the musical counts.

"I want the audience to hear the breath," he said, "because it helps them see where the movement originates. They can actually follow the movement better and usually even become more aware of their own breathing. It's also a way for the dancers and the audience to connect."

Forsythe's wife, Dana Caspersen, a longtime member of the company, has often danced "Duo," the second piece on the program, in which two women, sexily clad in shimmering black leotards, represent the hands of a clock. "They register time in a spiraling way," she said, "trying to make it visible and then they figure out how it fits into space and pull it into an intricate pattern."

Always interested in the ways stage design affects a dance, Forsythe choreographed "N.N.N.N." for four men, confining them to a narrow strip at the front of the stage. To almost inaudible music, they twist and contort their bodies in a mechanical manner that occasionally looks almost like slapstick, with rapid-fire changes in direction.

The grandest and most complex work on the program, "One Flat Thing, Reproduced," begins with the overwhelming sound of 20 metal tables being dragged across the stage by 17 dancers. From this wild introduction, it goes on to sweep one up in a maze of mesmerizing patterns.

"For years," Forsythe said, "I've been preoccupied with contrasting order and disorder. This was inspired by Robert Scott's failed expedition to reach the South Pole. The piece is like a storm they may have encountered. I choreographed an orderly conclusion. I imagine it is probably how Scott hoped his expedition would end."

Forsythe has high hopes for the program's reception. "Through the entire evening," he said, "the audience should be compelled to participate, listening and trying to anticipate what's going to happen. I switch from the strongly acoustic in the beginning to the strongly optical. You wouldn't be able to watch the final piece as well if you hadn't watched the three before it, because the last requires keen observational skills."

Isn't this a lot to expect of audiences? "If you go to a baseball game," Forsythe said, "and you look at the guy at bat swing, and then watch the ball fly out into the field as he rounds the bases, that takes concentration. I'm only asking people who come to see my dances to do the same thing."

Dana Caspersen and Ander Zabala portray a chance encounter in "The Room as It Was" with Ballett Frankfurt, at the Kennedy Center through Saturday."There's an awful lot of movement research that I've never had time for," says William Forsythe.