Chopin composed the Fantaisie-Impromptu in 1834, but it was only published after his death by his friend Julian Fontana in 1855. Chopin dedicated this piece to Fontana, who played a significant role in bringing many of Chopin's works to the public. The piece follows an A-B-A structure, with fast outer sections and a slow, lyrical middle section. It features complex rhythms, with the right hand playing sixteenth notes against the left hand's triplet eighth notes, creating a challenging and dynamic piece for pianists.