The closing days of 2008 mark the end of Alexei Ratmansky's five-year tenure as artistic director of the Bolshoi Theater's ballet company, a period marked by continued resurgence of the theater's formerly deflated eminence.

From Jan. 1 of the coming year, his center of activity moves to New York, where he is due to join the American Ballet Theater in the newly created position of "artist-in-residence." Succeeding Ratmansky will be his former ballet-school classmate Yury Burlaka, an expert in restoring choreography of the 19th century and long associated with a local dance company known simply as "Russian Ballet."

On Sunday, the Bolshoi plans to honor Ratmansky with a gala evening of ballet that is scheduled to include performances by members of both his present and future home companies, as well as leading dancers from St. Petersburg's Mariinsky Theater and the New York City Ballet.

Joining the Bolshoi in 2004, Ratmansky found a ballet troupe already well on its way to recovering from the doldrums of the 1990s. Ratmansky advanced the process of revitalization, diversifying the repertoire with a nicely balanced mixture of classical ballets, works by master choreographers of the 20th century and brand new choreography, including some superb examples of his own. Beyond that, he created new challenges for members of the existing company and enlisted a group of extraordinarily talented young dancers fresh out of ballet school.

Ratmansky was born 40 years ago in Leningrad and trained at the Moscow Choreographic Academy, from which he graduated in 1986. His career as a dancer began at Kiev's Shevchenko Theater of Opera and Ballet and continued by way of engagements as a soloist with the Royal Winnipeg Ballet in Canada and with Copenhagen's Royal Danish Ballet.

In the mid 1990s, Ratmansky began pursuing a parallel career as a choreographer. Among his earlier works were two for the Bolshoi, one of which, entitled "Dreams of Japan," received a Golden Mask Award in 1999. His superlatively beautiful setting of Sergei Prokofiev's "Cinderella" for the Mariinsky became a Golden Mask nominee four years later but was passed up for the award, rather unjustly in the opinion of many.

Ratmansky returned to the Bolshoi in early 2003 to stage what has surely become the hit of his career at the theater, an altogether newly choreographed version of Dmitry Shostakovich's ballet "The Bright Stream." Originally performed at what is now the Mariinsky in June 1935, it came to the Bolshoi later the same year but quickly disappeared from both stages following a newspaper editorial that denounced its depiction of high jinks on a collective farm as "falsehood." With a somewhat revised story, Ratmansky turned "The Bright Stream" into a joyful and often hilarious romp that has repeatedly captured the hearts of audiences both in Moscow and on numerous tours abroad.

Upon assuming the post of ballet artistic director in 2004, Ratmansky turned to yet another nearly forgotten Shostakovich ballet titled "Bolt." With a more serious plot concerning industrial sabotage, "Bolt" has never come close to achieving the success of "The Bright Stream," despite its many moments of comedy and a great deal of highly imaginative choreography.

The following year, Ratmansky came up with a setting of Stravinsky's "The Card Game," a brief, invigorating piece of abstract dance for 15 of the Bolshoi's younger soloists. Turning next to the 19th-century classic "Le Corsaire," he seamlessly combined his own original choreography with the surviving portions of an 1899 Mariinsky staging by Marius Petipa, as recreated by his current successor-to-be Burlaka.

Last summer, Ratmansky undertook the revival of a different sort of classic, a renowned ballet of the Soviet era called "The Flames of Paris." With all but some 20 minutes of the original 1932 choreography by Vasily Vainonen lost to posterity, the result proved to be largely Ratmansky's own newly minted work. As in the case of "Le Corsaire," his contribution artfully matched the remnants of a composition handed down from the past.

Two months ago, for his final choreographic work as Bolshoi ballet artistic director, Ratmansky staged "Russian Seasons," a completely original creation commissioned by the New York City Ballet, who danced its premiere in 2006. Set to a score by Leonid Desyatnikov with origins in folk music, it offered a profound look into the very heart of traditional Russian life and contained perhaps the most inventive and focused choreography to be found in any of Ratmansky's work to date.

Ratmansky has been hailed by experts far and wide as perhaps the most talented choreographer of his generation, and it has been Moscow's tremendously good fortune to serve as the focal point of his activity over the past five years. Thankfully, that good fortune will remain in part: In taking leave of his present post at the Bolshoi, Ratmansky has agreed to return from time to time in a new capacity as the theater's principal guest choreographer.