During his stay in Mannheim between October 1777 and March 1778, Mozart received commissions for two quartets with flute (K. 285 and K. 285a) – an instrument then much in vogue, not least because the Prince-Elector Karl Theodor of Bavaria played it as an amateur. A third quartet, K. 285b, was probably written in Vienna in 1786–87. These works hold a special place for flutist Anna Besson, who performed them on tour at the age of fifteen, among her very first concerts. To them she adds Hoffmeister's arrangement of the sonata K. 311, prized for the beauty of its central movement and the delicacy with which the publisher, a close friend of Mozart's, redistributed the keyboard writing between flute and strings.