Series I and II of the New Liszt Edition contain all Liszt's works for solo piano, and the appendices contain versions that differ significantly from the definitive version of the works. The supplementary volumes complement these first two series: they contain early versions of works for solo piano, compositions, album leaves, and unfinished works that have since come to light and are as yet unpublished. The first three supplementary volumes contain the collection of exercises entitled Technische Studien, which the composer himself intended to be in three parts, but which was published after Liszt's death - parts 1 and 2 in 1886 or 1887/1888, and part three, which had been considered lost, published many years later, in 1983.

In his technical exercises, Liszt always considered musical expression and tone quality to be more important than rapid, loud, and empty playing; this is indicated in a brief annotation before the first exercise. The exercises move through all the keys in a cycle of fifths, and aim to overcome all manner of problems of piano technique. The three parts form a single large whole, which is far more than a collection of technical formulae: it represents the culmination of the virtuoso instrumental tradition of the nineteenth century.

All three volumes include a detailed preface in German, English, and Hungarian, including new research findings and manuscript facsimiles, as well as critical notes in English. Along with the cloth-bound edition, a practical paperback version has also been published, the contents of which are identical.