The grundgestalt, a term of Schoenberg, referring to the initial material of a work that is organically developed through the entire work, is often employed in analysis and discussion of Beethoven and earlier Classicists, and is largely employed in studying the sonata, often described as the “most important design in tonal music”. In order to clarify the nature of Franz Schubert’s compositional process concerning the Wanderer Fantasy, op. 15, this study will explore the organic development of compositional matter from the piece’s motivic material, and the relationship between such material and the form of the work. Through Arnold Schoenberg’s concept of grundgestalt, or “basic shape,” Schubert’s music will be discussed from the perspective of melodic and harmonic relationships as well as form. It is not the intent of this paper to suggest that Schubert’s process is limited to this formula, but simply that Schoenberg’s concept, often applied to the music of Beethoven, is useful in understanding Schubert’s music as well.