The poetry of William Butler Yeats presents unusual problems for the general reader. Yeats drew heavily upon mystical and theosophical systems of a more or less arcane nature. Moreover, he often referred to events in his own life and in the history of modern Ireland which require elucidition for the non-specialist. A Reader's Guide to William Butler Yeats not only provides the background needed for an understanding of the works but also reveals the structure of images and meanings of the various lyrics.