YOU NEVER quite know what to expect when you venture into a performance by Improvisations Unlimited.

The program always opens with "The Process," a thoroughly unpredictable session during which the dancers create brief, on-the-spot pieces in response to verbal cues from their director, Meriam Rosen. As one can imagine, the results range from the amazing to the absurd. Even the more formally structured works on the program leave room for at least one improvised passage, meaning that no two performances of a given dance will ever be the same.

The eight-member company's winter concert at their home base, the University of Maryland, will introduce Improv fans to several new recruits and will feature a new work by Rosen. Entitled "Looking Back" and set to Robert Schumann's alternatively playful and melancholy piano suite "Kinderscenen" (as well as a tape collage of voices), the work stems from a memory/movement exercise that Rosen devised for her dancers. The program will also include pieces by New York artists Beverly Blossom and Jerry Pearson, and one of this area's most accomplished choreographers, Jeff Duncan.

I don't normally like to recommend work I've not yet seen myself but sources tell me that Shapiro & Smith Dance's "Couple Dances" are worthwhile indeed. Daniel Shapiro and Joanie Smith, both of them former soloists with the Murray Louis Dance Company in New York, have spent the last two years creating duets about relationships of all sorts. Many of them apparently make some wickedly satirical points.

IMPROVISATIONS UNLIMITED -- 9 p.m. Friday, 2 and 8 p.m. Saturday at the University of Maryland Studio EE Theater, College Park. Tickets $6 and $8. Call 454-4847.

SHAPIRO & SMITH DANCE -- 8:30 p.m. Saturday and 4 p.m. Sunday. The Dance Place, 3225 Eighth St. NE. Call 269-1600.