The study of twelve-tone and atonal music is a young discipline, because its subject, as music history goes, is a very recent arrival upon the scene. We measure our tradition in decades, rather than centuries, and, various spurious obituary notices to the contrary, twelve-tone composition is still a vital, if not particularly audible, part of today's musical culture. Thus, our subject is not easily subjugated, and its constant expansion defies circumscription. However, the very vitality of our subject has itself spawned a lively and diverse body of thought abut twelve-tone and atonal music, in large part because so many of the participants wear two hats. We need only remember that two of the brightest lights of the twelve-tone theoretical firmament are Arnold Schoenberg and Milton Babbitt to remind us that many of the proponents of twelve-tone and atonal music are themselves practitioners. The result is a wealth of engaging musical thought that ranges from considerations of the most general issues to the equivalent of a proud parent exhibiting photographs of its most recent offspring. In trying to offer an overview of the current state of research in twelve-tone and atonal theory I can only provide a personal perspective, colored by my affinities and preoccupations as a general proponent of this music, and admittedly infected by my own parental biases and enthusiasms. Nevertheless, I hope the following notes will provide a scaffold from which to view the growing edifice, bearing in mind that scaffolds are built to be dismantled when they are no longer useful. I find it useful to divide twelve-tone and atonal theory into four broad areas of concern. Most writings on twelve-tone and atonal music tend to concentrate on fewer than all of them, but in most cases tacit assumptions about the others may be inferred. These four areas will give us a way of viewing the wealth of articles that have appeared over the past several years, and will also allow me to highlight some of the issues addressed. My first area of concern is the parsing of the musical surface, the basic process of grouping events as intelligible entities. As we shall observe later, this is by no means a simple problem, although it is possible to get a great deal of analytical mileage by using common sense. The critical importance of considering surface grouping structures is brought out in a number of writings in explicit ways. William Benjamin is assiduous in this regard in Ideas of Order in Motivic Music, as is Stephen Peles in Interpretations of Sets in Multiple Dimensions: Notes on the Second Movement of Arnold Schoenberg's String Quartet No. 3. Interpretation of the musical surface has been a central concern of Christopher Hasty, who most recently articulated it in his presentation at the 1986 SMT conference, Material and Form in Webern's Twelve-Tone Music. but whose other writ-