Béla Bartók’s orchestral output is relatively compact: alongside the three piano concertos (1926, 1931, 1945) and the three-movement violin concerto (1938), it comprises primarily the Music for Strings, Percussion and Celesta (1936), the Divertimento for String Orchestra (1939), and the Concerto for Orchestra, completed in October 1943. The work’s premiere took place on December 1, 1944, at a concert given by the Boston Symphony Orchestra under Serge Koussevitzky at Carnegie Hall in New York. “The general mood of the work,” Bartók wrote in the program notes, “represents, apart from the jesting second movement, a gradual transition from the sternness of the first movement and the lugubrious death-song of the third, to the life-assertion of the last one.” To many critics, the concerto appeared to be a step backward; they viewed Bartók’s move away from the radicalism of his middle-period works and his turn toward classical simplicity and clarity as a concession to American public taste, mistaking his newfound serenity and composure for weakness. Yet this relaxation of his musical language had already been foreshadowed in the violin concerto and the Divertimento. Today, we regard the Concerto for Orchestra as a work of supreme compositional maturity.