We have seen folk troupes that are more polished and more opulently outfitted, but few as beautiful, as vital or as beguilingly natural as Abrasevic, the Yugoslavian ensemble that made its first Washington appearance at the Kennedy Center Saturday night.

Founded in 1905, Abrasevic functions as a conservatory as well as a performing company in its homeland. Both aspects are reflected in the touring dance unit, which includes 20 remarkably proficient and exuberant youngsters ranging from 8 to the midteens, along with highly skilled adults of both sexes.

The key to the group's excellence lies in the taste and intelligence of the choreography, most of it by Abrasevic's director, Dragoslav Dzadzevic. Traditional folk motifs are the basis, but they are fashioned into exceptionally flavorful and interesting dances with a minimum of gimmicks.

The music too, splendidly set forth by a small ensemble, was enchanting in its metrical pungency, and the arrangements are free of schlock and overamplification.

The programming was uncommonly varied, drawing as it does on the richly heterogeneous strains of Yugoslav culture and those of neighboring nations as well. A last kudo -- someone here has the wit to realize that dances in a slow tempo (the lovely "Biljana," for example) or in silence (a men's Macedonian dance) can be equally or even more captivating than the relentless frenzy which dominates so many other folk troupes nowadays.