The American Composers Orchestra (ACO) is an American orchestra based in New York City. It is the only orchestra in the world dedicated solely to the creation, performance, preservation, and promulgation of music by American composers. Through its concerts at Carnegie Hall and other venues, recordings, radio broadcasts, educational programs, New Music Readings and commissions, ACO identifies today's brightest emerging composers, champions prominent established composers as well as those lesser-known, and increases regional, national and international awareness of the infinite variety of American orchestral music, reflecting geographic, stylistic, and temporal diversity. ACO also serves as an incubator of ideas, research and talent, as a catalyst for growth and change among orchestras, and as an advocate for American composers and their music. To date, ACO has performed music by 500 American composers, including more than 100 world premieres and newly commissioned works.