This monograph provides an in-depth examination of the background, musical, and performance issues related to Duke Ellington’s wordless melodies, as well as epigrammatic biographies of Ellington and three female vocalists whose voices he employed as instruments: Adelaide Hall, Kay Davis, and Alice Babs. As early as the twenties, Ellington innovatively used the voice as a wordless instrumental color—an idea he extended into both his secular and sacred works. His iconoclastic instrumentalization of the soprano voice in compositions such as “Creole Love Call”, “Minnehaha”, “Transblucency”, “On a Turquoise Cloud”, and “T.G.G.T.” merits consideration by scholars and performers alike; these artistically complex melodies offer valuable insights into Ellington’s organic and collaborative compositional process. Although Ellington’s wordless melodies for the soprano voice have fallen on the periphery of discussions on twentieth-century American music, perhaps out of sheer obscurity, the need for alternative teaching and performance materials gives rise to a host of topics for further study regarding these pieces. Assimilating Ellington’s programmatic and mood pieces for the instrumentalized soprano voice into the canon of chamber repertoire opens a new arena of scholarly and artistic endeavor for the trained singer. Therefore, central to this study are the following considerations: context, pedagogical challenges (range, tessitura, vowels, phrase length, etc.) nature of accompaniment and instrumentation, form, and the nature of Ellington’s vocal writing as it pertains to the wordless obbligato and concert works featuring the wordless voice including, “Minnehaha,” “Transblucency,” “On A Turquoise Cloud,” and “T.G.T.T.” aka “Too Good To Title.” This study evaluates Ellington’s technique of casting the wordless female voice in unique musical contexts via musical analysis, as well as pedagogical and interpretive assessments of selected Ellington pieces,. The resultant amalgam of musical identities, both instrumental and vocal, fostered creative polyphony and epitomized the coined “Ellington Effect.” The following analysis centers on a chronological survey of Ellington’s wordless melodies performed and recorded by Adelaide Hall, Kay Davis, and Alice Babs. The goal of this project is to present a study in historical context and significance, style, device, and pedagogical/performance considerations of those works that employ the flexibility, technique, and aural training of the studied singer with instrumental jazz idioms in a cross-genre context.