Cindy McTee's Symphony No. 1: Ballet for Orchestra is composed primarily of pitch materials from the octatonic collections that contain both diatonic and non-diatonic relationships in the themes, harmonic content, and larger structure of the symphony. Because the octatonic collections contain the potential for both diatonic and non-diatonic relationships, the piece is argued to have octatonic structure, as the octatonic collection is capable of producing both relationships. The second chapter contains a review of the literature, focusing particularly on the work of Arthur Berger, Pieter C. van den Toorn, Richard Taruskin, and Allen Forte. Next, the octatonic structure of the symphony is shown in the thematic material. Finally, the harmonic support and large-scale structure of the piece are shown to contain octatonic relationships as well.