Opera Australia Orchestra associated with working in the Sydney Opera House orchestra pit. The OAO provides orchestral accompaniment to Opera Australia and The Australian Ballet and is one of the few opera orchestras in the world that operates in a repertory style of operation over a period, or season, that can be some months in length. Other opera houses that operate this way are The Metropolitan Opera in New York City, The Royal Opera House Covent Garden in London and La Scala, Milan. 'Repertory style' also infers that over time, certain composers and operas become considered 'standard' to the working operation of the
Metropolitan Opera House (Lincoln Center) premieres of operas, including John Corigliano's "The Ghosts of Versailles", Phillip Glass's "The Voyage" and the US premiere of Nico Muhly's "Two Boys" in 2013. When the Metropolitan Opera is on hiatus, the Opera House is home to the annual Spring season of American Ballet Theatre (ABT). It regularly hosts touring opera and ballet companies including the Kirov, Bolshoi, and the La Scala companies. In addition, the Met has presented recitals by Vladimir Horowitz, Renée Fleming, Kathleen Battle and others. Philip Glass's "Einstein on the Beach" was staged independently at the Met in 1976. Concerts by Barbra Streisand, The Who,