At the end of his short life Franz Schubert impressively illustrated, in his collections of “Impromptus” and “Moments musicaux”, how lyrical-songlike form could be rendered on the piano. The Impromptu in A flat major op. 90 no. 4 numbers among the most popular pieces in the piano repertoire. The player using our Urtext edition can revel in the purling downward arpeggios and delight in the expressive power of the lyrical and expressive c sharp minor Trio.