Though the origin of Bach’s sonatas for flute and harpsichord is uncertain there has also been considerable debate about their genre. The first three are often called ‘Sonaten auf Concertenart’—sonatas in concerto style—a hybrid genre that became popular between around 1720 and 1740, so Bach may have been deliberately experimenting with form in these works. The Sonata in E flat major, BWV 1031, with its lovely siciliano, is perhaps the most popular of the flute sonatas, holding a special place in the repertory, but all offer a fascinating insight into Bach’s use of the sonata genre and a wealth of inventive music.