This dissertation analyzes the original composition Radial, which is scored for alto saxophone solo, small orchestra and live electronics. Multiphonics are a common feature on the aural surface of Radial. This analysis will show that alto saxophone multiphonics are also a primary structural element in the work, hierarchically organizing the timbres, harmonies, instrumental interactions and large-scale form of the score. Interestingly, no source suggests how multiphonics can be an independent organizational force. Numerous book length multiphonic catalogues for diverse instruments give fingerings for these sounds and describe them as harmonies so that they can be fitted into harmonic contexts, and a small but significant scientific literature on multiphonics discusses the acoustic principles underlying these sounds, but no document considers their independent structural potential. After providing a general account of multiphonics and their relation to harmonic and inharmonic sounds, this dissertation will propose an answer to that problem by drawing together concepts from American experimental music, spectralism and cognitive music theory, with Radial reviewed as an example of this method in action. Historical issues and a broad range of implications for this research will also be discussed.