When Kenneth Rinker left Washington in the late 1960s, after graduation from the University of Maryland and years of rigorous training under a number of the area's finest teachers, he was already an outstandingly fine dancer. He's become an even better one since, as he demonstrated resoundingly last night with the debut appearance of his own Kenneth Rinker Dance Company in the Kennedy Center's Terrace Theater, under the aegis of the Dance America series.

The evening began, in the first of two world premieres, with a Rinker solo to the strains of "Strike Up the Band," and it was a stunner. He went from mercurial velocity to lazy loping and back in two blinks. He'd careen into a position of imperiled balance, and right himself with an instant flip of axis. He'd drop to a near-supine angle in one second, and wheel off to a flurry of jittery steps in the next. The bristling energy and insouciant ease of it all was breathtaking.

Slim, trim and sandy-haired, you could still take him for Joe College. His slenderness and graceful laxity of carriage make him look tall on stage, though his height isn't exceptional and his movement is marked by a fusion of razor-edge precision and rubbery plasticity that was much nurtured in his seven years as a leading dancer with Twyla Tharp's company. Rinker is one of a kind, but he shares with the other members of his troupe--which he formed in 1979 after leaving Tharp--not just technical expertise but an engagingly youthful sangfroid. They all dance like they're enjoying the hell out of it.

That quality is infectious, and it was the dancing that carried the evening through its choreographic vagaries. On the evidence of last night's new pieces, Rinker has a spry and prolific but perilously unruly creative imagination--ideas burst forth in exuberant combustion, but run away with themselves without ever coming to coherent focus as a whole. Moment by moment it's exciting stuff, but one waits in vain for a sense of editorial control or integrating form.

The influence of Tharp is strong--in the incessant, detailed activity, the loose-jointedness, the flux of exits and entrances, the pop dance imagery, and the individuation of movement but equality of weight accorded to each dancer in the ensemble.

Of the two premieres, "(Fable) in Four Fugues" was the more rewarding, and the more diversified in tempo and dynamics. It's got an attractive original score for piano, electronic keyboard and taped voices by Sergio Cervetti, the former Washingtonian who's long been Rinker's close associate and collaborator. The music adds and subtracts burbling layers of sound over iterated rhythmic foundations. The six dancers wear layered attire, sometimes exchanging garments or doffing parts of them. The work has the flavor of children's games about it--there's a lot of hand-clapping, a suggestion of competition, an atmosphere of genial frolic. Sometimes the ensemble aligns briefly into unison patterns, but mostly it's partitioned into groups or single dancers doing their own thing. What the piece mostly lacks is overall shape, a sense that its progression of phases is governed by something other than random juxtaposition.

The other work, "Suite Swing," set to popular tunes by Gershwin, Rodgers and others, both as recorded by the Benny Goodman Band and as played live by Cervetti, belongs to the already supersaturated realm of '40s nostalgia, as cultivated by Tharp and many others. Despite many bright passages, like Rinker's opening solo, the piece adds little that's fresh to this overcrowded genre.