21.   He is now principal guest conductor of the Trondheim Symphony Orchestra in Norway and next year will become music director of the Deutsch Kammer Orchestra in Bremen.

22.   He was also the principal guest conductor of the New Zealand Symphony and the artistic director of the Solistas de Mexico in recent years.

23.   In an unusual collaborative partnership, Spano will share responsibilities with San Francisco Opera music director Donald Runnicles, who has been named ASO principal guest conductor.

24.   In Dallas he was also a principal guest conductor of the Pittsburgh Symphony and the director of the National Opera of Mexico.

25.   Itzhak Perlman, principal guest conductor of the Detroit Symphony, has been an annual visitor to Tanglewood throughout his career.

26.   Persuading Bernard Haitink to accept the position of principal guest conductor was a major coup of the Ozawa era.

27.   Persuading Bernard Haitink to accept the position of principal guest conductor was a major coup.

28.   Still, while she recently renewed her contract as principal guest artist of the Royal Ballet, she continues to search for new challenges.

29.   Sylvie Guillem, a graduate from the school who is now principal guest artist at the Royal Ballet, said that parents often applied pressure on their children.

30.   The BSO principal guest conductor Bernard Haitink, for example, began to concentrate on opera only after decades in the concert hall.