Poets' working drafts and their comments on their processes indicate overwhelmingly that they, like experienced writers of other genres, are extensive revisers. The biggest difficulty with the term "revising" is that it designates both the changes made to a text and the mental processes and attitudes that underlie these changes. Even the nineteenth century poets who described their process of writing as spontaneous (Shelley, for example) left manuscripts that are heavily reworked. In the twentieth century poets' working papers, as well as their individual comments, testify to the extensive nature of their revising process. Poetic revision appears to entail deletion rather than addition--a process of tightening rather than elaboration. While poets revise both internally, for themselves, and externally, for a reader, this dichotomy is most appropriate for describing the process of moving a text from expressive into transactional, rather than into poetic, discourse. To account for the poetic dimension of revision, a three-part rather than a two-part model is needed. Poets revise not only to discover what they know, or to communicate this to an audience, but to uncover what the poem knows. Poets play with words and are extensive revisers precisely because they are fascinated by language. (NKA)