With a versatility and naturalness as appropriate to the salon as to the concert hall, Chopin's Nocturnes rank among the works that brought the composer not only fame, but also enormous renown. The demand for them was correspondingly great, and thus it will come as no surprise to learn that Chopin released the op. 48 Nocturnes, written in 1841, in that same year and simultaneously in France, England and Germany. For present-day editors, this brings the difficult task of evaluating the variants present in the different first editions. As far as opus 48 is concerned, the task has been made somewhat easier by the re-emergence of the long-lost autograph of the works. We have thus been able to use it as a significant source for Henle's Urtext edition.