When the five dancers of Free Association walk on stage and start to dance, they have nothing planned, nothing choregraphed.

"That's our challenge - not knowing what we're going to do next," says Margaret Ramsey, artistic director and founder of the company.

All the Free Association performances are improvisations: free-wheeling, intermission-less sessions in which movement impulses are transmitted from one performer to the next, and from dancer to musician and back, and bounced off the audience.

The group also uses costumes, props and voice to carry the movement patterns through changes of tempo and intensity in a process akin to free association - and hence the name.

Free Associations will perform at Lisner Auditorium, 21st and H streets NW, at 12:15 p.m. Tuesday as part of the theater's lunchtime series. What can you expect to see?

Just about anything.

At a February performance at Mount Vernon College Hand Chapel, company member Jack Guidone sang "Rock of Ages" from a balcony, while Wendy Woodson rocked back and forth on the floor below.

Barbara Mueller sang to a chair and slowly rolled across the stage, while Jim Brown practiced leaping over her body.

Mood and energy can change in a split second, as when Brown with a hideous grin stopped a line of leaping dancers in midair. Or a scene can wind down slowly into a dead spot, with dancers moving aimlessly till something clicks. "We don't try to translate emotion or tell a story," explained Ramsey. "It's not the old school of improvisation that says, "Well, today I'll be a rainbow." Instead, we start with the movement itself, and see where that leads."

According to Ramsey, one thing is for sure - "the humor always bubbles to the top."

Ramsey was first exposed to improvisation in 1961, while studying with Mary Wigman in Berlin on a Fullbright scholarship. When Ramsey began to teach, she used improvisation to help beginning students get the feel of dancing.

In 1974, Ramsey and four students from her dance and mime classes at George Washington University presented a student showing at the Dimock Gallery. Free Association has been performing ever since - with as many as 30 appearances a year.

Two of the original company members remain: Barbara Mueller, who teaches at Montgomery College and in local dance studios, and Jack Guidone, a drama graduate of George Washington University who has performed at New Playwright's Theater and the Washington Project for the Arts.

In the past year, two new members have joined the company: Wendy Woodson, who teaches modern dance at the Y.W.C.A. and recently choreographed and directed a dance for eight women at the Washington Project for the Arts, and Jim Brown, who now is choreographing musicals for drama departments in Maryland and the District.

Four of the five company members have master's degrees in dance, but that's not why Ramsey selected them.

"To improvise, you need a real presence on stage as well as a tremendous range of movement," she said. "You have to be a very confident person, because the risks are incredible."

The choice of performers is mystical indeed, because company members must be able to read each other's minds if they are to pick up movements and ideas before the critical instant has passed.

To make sure the chemistry is there, the group meets two nights a week. After a warm-up period, the dancers may work on a specific movement pattern, such as lifts and crawling, or on relating to another company member.

Or they may use improvisation to explore concepts such as timing, shape, volume, impulse - the elements that make up traditional choreography.

What makes Free Association different is the spontaneity - the fact that what happens next may be a crashing bore or a complete surprise.

There can be terrifying moments, admits company member Wendy Woodson, but each is a new experience in self-knowledge.

"There can be terrifying moments in a staged work, too - you can forget the movement," she explained. "In improvisation, you can always go with your instinct."