Bartók taught piano at the Music Academy in Budapest from 1907 to 1934. In his first years as a professor the Budapest music publishers Rozsnyai and Rózsavölgyi commissioned him to prepare so-called instructive editions (including suggestions, commentaries and fingerings for the performer) of several classics of the piano repertoire, altogether more than two thousand pages of music. Bartók's editing reflects contemporary ideas about performance, but is for the most part more detailed and elaborate than in other similar instructive editions at the turn of the century.