The as-yet-unnamed Haas work, scheduled for March 2006, was commissioned by the Cleveland Orchestra. The season also includes the American premieres of Diptych by Julian Anderson, the orchestra's newly appointed Daniel R. Lewis Young Composer Fellow; Chen Yi's Si Ji (Four Seasons), which the orchestra will also debut at the Lucerne Festival in August; and Marc-Andr_ Dalbavie's Piano Concerto, with Leif Ove Andsnes.

The Mozart on the schedule includes two weeks of piano concertos performed and conducted by Mitsuko Uchida, the orchestra's artist in residence, as part of a five-year cycle of the composer's concertos.

Also among the guest soloists on the schedule are pianist Pierre-Laurent Aimard; violinist Leila Josefowicz; sopranos Heidi Grant Murphy, Felicity Lott, and Karita Mattila; mezzo-soprano Lorraine Hunt Lieberson; and baritones Thomas Hampson and Simon Keenlyside.

Music director Franz Welser-M‹st will conduct 12 weeks of concerts, leading, among other works, Bach's St. Matthew Passion, Ives' Second Symphony, Messiaen's TurangalêÎla-symphonie, Thomas Ads' Chamber Symphony, Mahler's Symphony No. 9, and the Haydn Trumpet Concerto.

Guest conductors include the New York Philharnmonic's Lorin Maazel, music director of the Cleveland Orchestra from 1972 to 1982; Robert Spano, music director of the Atlanta Symphony; Michael Tilson Thomas, music director of the San Francisco Symphony; Vladimir Ashkenazy, the orchestra's former principal guest conductor; Donald Runnicles, music director of the San Francisco Opera; and Osmo V‹nsk‹, music director of the Minnesota Orchestra.