‘I am planning a symphony or a string quartet, I do not know which I shall decide upon,’ Tchaikovsky wrote in a letter dated 21 September 1880. The work, eventually entitled Serenade for Strings, follows the classical four-movement pattern of symphonies and string quartets, with a waltz functioning as a ‘scherzo’ in the second movement. The composer gave each movement a different name. The first movement is called ‘Pezzo in forma di Sonatina’ (Piece in Sonata Form). Beginning with bright, densely-wrought string sonority, the slow introduction assumes a particular emphasis in the work: the starting movement returns several times, including at the end of the finale, serving as a frame to the entire composition. The Serenade for Strings is characterised by a delicate, often polyphonic fabric where the string-quartet ‘impulse’ is evident in almost every measure. The phenomenal ‘Waltz’ movement had to be encored at the world premi?re and has virtually lived on as a piece in its own right. The slow movement (‘Élégie’) brings new colours to the Serenade, and it is as if the composer were evoking a Russian folk song. The closing movement, as the title ‘Finale (tema russo)’ indicates, is truly based on a Russian folk song – two in fact: one in the slow introduction, and the other as the main theme of the fast sonata movement. Tchaikovsky has a surprise for the end of the finale. He makes it clear with the return of the slow introduction of the opening movement that the introduction and the fast finale theme are based on the same four-note motif.