This dissertation provides an analysis of Island Prelude based on a method of analysis prescribed by the composer. The method, Energy Line Analysis, is essential to an enlightened performance. The content of this dissertation includes: biographical information, compositional influences, Joan Tower style periods, her works involving the oboe in a major role, and an Energy Line Analysis chart of Island Prelude. Island Prelude represents Joan Tower's musical language, the understanding of which is essential in an interpretation of her music.