LIZ LERMAN is in town. For a change. The choreographer and her contemporary dance company, the Takoma Park-based Liz Lerman Dance Exchange, have a schedule of performances and community residencies across the country that keeps them on the road for much of the year. That will change -- for a weekend, anyway -- when the troupe performs "Scores for Salt and Snow: Dances Since 2002" on Saturday and Sunday at American University.

The first of three Lerman works that make up the program, "Anatomies and Epidemics" is an alternately portentous and playful work punctuated by infectious laughter -- infectious in the medical sense, that is. Set to a score by Alan Hovhaness, Spike Jones and Andy Teirstein, the piece originated during a residency the company conducted shortly after Sept. 11, 2001. "Many of the participants were New Yorkers," Lerman says. "They were very raw."

That sense of inchoate emotion permeates the piece, which combines dance and spoken-word elements to explore the distinction between anguish and mirth. "We basically stop breathing when we laugh," Lerman says. "If a person is laughing and you can't hear them, you can't tell whether they're laughing or crying." In "Anatomies and Epidemics," laughter moves through the population of dancers like a contagion.

Composer Leonard Bernstein provides both the music and the inspiration for "Dances at a Cocktail Party." Lerman says she thoroughly enjoyed researching Bernstein, whom she calls "one of the first postmoderns." Much like Lerman herself, the composer-conductor-author refused to be bound by convention. "When people said, 'You can do this, you can't do that,' he said, 'Screw that!' " Lerman says. The piece, which Lerman calls "loose and sketchy," is set to several of Bernstein's lesser-known works.

Both "Dances at a Cocktail Party" and "Anatomies and Epidemics" were commissioned by the Tampa Bay Performing Arts Center, the latter, aptly, for its "Age of Anxiety" festival.

The program's final work, Lerman says, is "for adventurous audiences." Titled "Nature/Nurture: Environment and Character," the piece was inspired by the company's site-specific work at the Hirshhorn Museum and Sculpture Garden in conjunction with installation artist Ann Hamilton's "at hand" exhibit.

Though the piece is in flux, Lerman is loath to call it a work-in-progress. "It's more like a long journey that started last fall and won't be completed until 2006," she says. "There's a 24-month dance going on, and people can drop in for 10 minutes -- it feels like that." As its title suggests, the "movement-based" and "mysterious" work is thematically related to another developing Lerman project, a dance about the human genome. (Lerman and company are at work on another site-specific work in conjunction with a second Hamilton show, "corpus," which opens next month at the Massachusetts Museum of Contemporary Art.)

Still, the most unusual thing about this program may be the opportunity to see it locally. "We do so much touring and so many residencies that when we get to do a concert at home, it's pretty unique," Lerman says.

LIZ LERMAN DANCE EXCHANGE -- Performs "Scores for Salt and Snow: Dances Since 2002" Saturday at 8 and Sunday at 2 at American University's Greenberg Theatre, 4200 Wisconsin Ave. NW. 202-885-2587.

Choreographer Liz Lerman and her Liz Lerman Dance Exchange have traveled across the country for much of the year.Martha Wittman of the Liz Lerman Dance Exchange, which will perform "Scores for Salt and Snow: Dances Since 2002" at American University.