It's been a little more than a year since the American Ballet Theatre was last here, but it seems longer somehow, perhaps because we've had such a slew of other ballet troupes in town meanwhile. At any rate, ABT's return to the Kennedy Center Opera House last night, commencing a two-week engagement, felt all the more welcome in the wake of so extended an absence.

There are, after all, only a handful of companies in the world on this level, and among them, ABT has been our most constant visitor. Apart from the particular joys and merits of any given performance, the reappearances by ABT are indispensable reminders that the highest standards of classical ballet continue to be pursued and attained.

Pursuit is one thing, of course, and attainment another, and there's bound to be fluctuation. Last night wasn't free of flaws or disappointments. Still, it was remarkable that the company could look as fresh as it did on this opening night, given a grueling national tour and the eight weeks at New York's Metropolitan Opera House that preceded the Washington run. And that freshness, that capacity for rejuvenation in the wake of endless repetition, is part of what constitutes the greatness of ABT.

The program looked as though it were designed to be a model showcase for the Baryshnikov era at ABT, that is, for the period since the fall of 1980 when Mikhail Baryshnikov took over as the troupe's artistic director. Heavily represented among the dancers were those like Cheryl Yeager, Amanda McKerrow and Johan Renvall -- all promoted to principal rank since ABT was last in Washington -- whose careers have been specially propelled by Baryshnikov, as well as others, such as Robert Hill, Ricardo Bustamante and Christine Dunham, who have been edged into prominence even more recently. Also conspicuous among the performers was Argentine-born, 1985 Moscow Gold Medalist Julio Bocca, the latest ballet wunderkind, hired by Baryshnikov for ABT just last October.

The program, too, bore the Baryshnikov imprint -- one 19th-century classic, "Paquita," as staged "after Petipa" by Baryshnikov's former Kirov Ballet colleague Natalia Makarova; one virtuoso pas de deux ("Sylvia") in the Petipa manner, credited in the program to Andre' Eglevsky but known to all as the work of George Balanchine; and modern masterpieces by Balanchine and Paul Taylor recently acquired for the ABT repertoire.

It was as if the evening were setting forth Baryshnikov's ABT credo: "So you see, it is possible to have a world-class ballet company in this country with young, American-trained dancers as its headliners; without any foreign, big-name guest stars; and with a repertory buttressed by first-class choreography of both the past and the present."

It was fascinating to see ABT's "Paquita" again so closely on the heels of last year's Kirov Ballet visit. Martine van Hamel, creating her own majestic space with each movement, and her partner Kevin McKenzie, looking more at ease than ever with classical bravura, were quite splendid as the lead pair. But though this is Baryshnikov's company, and the piece is staged by Makarova, the ABT dancing no more resembles the present-day Kirov than the White House does the Kremlin. This is decidedly Americanized Petipa, at once more mechanically efficient, upbeat and athletically brash than the Russians, but also less subtle, elegant and stylistically taut. Carla Stallings and Dunham were especially impressive among the variation soloists.

The eternally youthful-looking Yeager was beautifully matched with Bocca in the "Sylvia" duet. The absolute assurance of his support allowed her to take risks with her phrasing and rhythm, and to milk the choreography for its sly coquetry. Bocca himself is undeniably a phenomenon -- a dancer who takes to the air as boldly and easily as this, who lands as neatly and with so soft a rebound, who makes a grande pirouette look as truly grand, and all this with as much nobility and musicality as Bocca exhibits, is a rare bird in any age. Artistic depth is hard to estimate from a showpiece like this one, but clearly Bocca has the makings of an extraordinary dancer; we'll be getting a better idea of his range as the run progresses.

Both Taylor's "Sunset" and Balanchine's "Stravinsky Violin Concerto" were transpositions -- that is, modern works created for troupes other than ABT -- and both performances showed how difficult it is to retain the original flavoring. They are both works of such craft and profundity that much of the formal substance and emotional import survives the transfer. In both cases, however, the overall impact seem diminished.

The wrenching "Sunset," with its images of wartime romance and sorrow, had its powerful "on" moments, when the dancing seemed at one with the choreographic utterance, but also its "off" passages, when the dancers appeared more concerned with getting the moves executed than with what they were about. Outstanding in the cast were Hill, John Summmers, Renvall, Dana Stackpole and Kathleen Moore.

McKerrow, Leslie Browne, Hill and Bustamante were the admirable leads in the Balanchine. But neither the principals nor the ensemble quite captured the constructivist look the New York City Ballet aptly gives this work, as if the choreography was a configuration of wire, glass and metal. And the two piercing duets called "Aria I" and "Aria II" need more of a contrast of texture and dynamics than this pair of couples was able to furnish.

Both works, the Taylor and the Balanchine, are tonics for the body and soul of ABT, as well as its audience; the longer they are lived with, the larger the benefits they're likely to bestow