This dissertation focuses on three of Busoni’s late orchestral works known as “orchestral elegies”: Berceuse élégiaque (Elegie no. 1, 1909), Gesang vom Reigen der Geister (Elegie no. 4, 1915), and Sarabande (Elegie no. 5, 1918-19). The study seeks to provide a better understanding of Busoni’s late style as a crucial bridge from late nineteenth-century chromaticism in the works of Liszt, Wagner, and others to the post-tonal languages of the twentieth century. At the heart of this study lies a particular concept that forms the basis of many characteristic features of Busoni’s late style, namely the concept of polyphonic harmony, or harmony as a cumulative result of independent melodic lines. This concept is also related to a technique of orchestration in which the collective harmony is sounded in such a way that the individual voices are distinct. In the highly personal tonal language of Busoni’s late works, passages often consist of a web of motives weaved throughout the voices at the surface level of the music. Linear analysis provides a means of unravelling the dense fabric of voices and illustrating the underlying harmonic progressions, which most often consist of parallel, primarily semitonal, progressions of tertian sonorities. Chapter 1 provides a backdrop …