Christian Wolff is now the sole living composer from the New York School of composition from the middle of the 20th century, a group that included John Cage, Morton Feldman, and Earle Brown. Wolff gives his players certain amounts of freedom in decisions during performance. Apartment House gave the premiere of Duo 10 (Summer Days) May 2014 in London. Two performance scores are needed to perform the 9-minute duo.