Kellogg will also be leaving his post as artistic director of Glimmerglass Opera in Cooperstown, New York, at the end of the 2006 summer season, a spokesperson for Glimmerglass confirmed. When he departs, Kellogg will have led the highly regarded festival company for 27 years, as general director from 1979 to 1996 and as artistic director since 1996.

In a statement, the 68-year-old Kellogg said that he was ready to turn the leadership of the two companies over to someone else.

"This has been a hard decision," he said, "but I will have run two opera companies for 29 years, and that's probably enough—for me and for the profession. It's been a wonderfully exciting and satisfying time, and I've had the chance to meet extraordinary people, but it's mostly a 15-hour-day, seven-days-a-week job that is probably better suited to someone 45 years old."

During Kellogg's tenure, NYCO has burnished its reputation as a center for groundbreaking productions, particularly of new American works and Baroque operas. NYCO has added 62 productions to its repertoire under his leadership and presented the world premieres of Deborah Drattell's Lilith and Charles Wuorinen's Haroun and the Sea of Stories and the New York premieres of operas by Michael Torke, Jake Heggie, and Mark Adamo. Since 1999, the company has also hosted the annual VOX festival, showcasing early versions of new American operas.

Kellogg has also spearheaded NYCO's efforts to find a new home created with opera in mind. (NYCO shares the New York State Theater with New York City Ballet.) In 2003, the company submitted an unsuccessful proposal for a new opera house on the former site of the World Trade Center. More recently, NYCO has reportedly discussed building a new home closer to Lincoln Center. In his statement today, Kellogg said that "although nothing can be confirmed or discussed specifically at this point, I would say that our finally getting a new theater is more likely than not. "

At Glimmerglass, Kellogg oversaw the creation of the Alice Busch Opera Theater on the shores of Otsego Lake and the world premiere of William Schuman's A Question of Taste, the American premiere of Mozart's Il re pastore, and the world premiere of the triptych Central Park. Over the last ten years, Kellogg's joint leadership of NYCO and Glimmerglass allowed for a close partnership, with 30 productions originating at Glimmerglass before traveling to New York City Opera.

Born in Hollywood, California, Kellogg studied at the University of Texas, the Sorbonne, and Columbia. Before joining Glimmerglass, he was a French teacher and administrator at the Allen-Stevenson School in New York.