"The Companion to Phonology" will be the major reference work of the field, drawing together nearly 150 contributions from almost all of the globally recognized, leading scholars in an estimated five-volume set. The international editorial team represents a diverse range of approaches and methodologies to the field, with the objective of creating a truly theoretically balanced work that will be of use to all phonologists and linguists. Different from all handbooks and other reference works for phonology which are available at present, the focus will be on empirical facts, rather than on theoretical insights. The Companion will function as a touchstone for future phonological theories: whenever somebody wants to propose a new theory for some phenomenon, she will be able to find all the relevant facts and insights which need to be accounted for in this work. The work will be organized thematically, and by volume: I. The Segment and Below II. The Segment and Above III. Changes and Processes IV. Interfaces V. Methodologies. In terms of competition, there is no other work currently available with this scope. There are large encyclopedic works covering the field of linguistics, such as "The Encyclopedia of Language and Linguistics", second edition, edited by Keith Brown (Elsevier, 2005); the approach and scope of this sort of work is clearly distinct from the proposed Companion, which is comprised of essays of 8,000- 10,000 words each to allow a fuller exploration of each topic. The Companion is not intended to be encyclopedic, but to offer an overview of the field as it currently stands. Shorter reference works such as the "Blackwell Handbook of Phonological Theory" (edited by John Goldsmith, 1996), or the "Cambridge Handbook of Phonology" (edited by Paul DeLacy, CUP, 2007) differ most obviously in their scope: "Goldsmith's Handbook" has 32 articles in it; DeLacy's has 25; a larger work allows more depth, nuance, and information. The Companion is also theoretically positioned as a work primarily for researchers.