This study examines the Piano Concerto in C sharp, Op.17 (1923), by Erich Wolfgang Korngold (1897-1957), in light of developing variation, techniques that transform motivic ideas and create musical continuity in this work. The troublesome reception history of Korngold’s piano concerto derives from its complex musical features, which have created difficulties in understanding and evaluating this piece. Consequently, critics and scholars often label the highly sophisticated yet tonal musical language in this piece a residue of Romanticism from the nineteenth century. In this document, in contrast, examination of motivic development and connections in Korngold’s piano concerto reveals thematic and structural coherence in light of Korngold’s idea of modernity. This study provides a historical and technical survey of developing variation and discusses Korngold’s implementation of these techniques in his early compositions and the piano concerto. By doing so, this study recognizes the progressive aspect in Korngold’s music.