The works brought together in this volume provide an example of the evolution of keyboard instruments: the first pieces were written for the harpsichord, two of them for an instrument equipped with the "Viennese bass octave", which allowed playing with one hand chords going beyond the hand gap. Our edition attaches to these passages, in the form of notes, proposals for execution. For later works, it is the “Hammerklavier”, the hammer piano, which comes into play. Haydn also willingly arranged his own compositions, for example the "Largo assai" from the quartet "the Horseman" for the piano. The fingering of this amplified, fully revised and corrected Urtext edition is by Christine Schornsheim, specialist in the practice of historical execution.