In Volume I/9 of the New Liszt Edition the definitive ten-movement version of the piano cycle Harmonies poétiques et religieuses was published in 1981. On several occasions Liszt mentioned that he attached particular importance to this cycle, and this is confirmed by the fact that he devoted almost two decades (1835-1853) to its composition. This Supplement volume of the New Liszt Edition initiates the reader into the mysteries of the cycle's genesis, publishing 17 completed pieces written for it and 6 that have survived as fragments, together with the album leaves belonging to them. The works composed between 1840 and 1848 also reflect the various concepts of the cycle and the prior history of the movements included in the final version, more than one shows Liszt's skill as an improviser. Among the compositions that survive in manuscript there are gems such as the hitherto virtually unknown Piano piece in G flat major, conceived in a moment of unselfconscious happiness. Others waiting to be discovered include the Piano piece in C minor and the enchantingly beautiful prayer, Litanies de Marie, of which two versions were written.