Lee, Byung-Gun, Natural Derivational Phonology, Seoul: Seoul National University Press, 2013, x+281Pp

In this book, the framework of Natural Derivational Phonology (NDP), proposed by the author, is introduced. NDP is a constraint-based model incorporating serial derivation, so it departs from standard Optimality Theory (Prince and Smolensky 1993/2004) (OT). It attempts to deal with problems that arise from extrinsic ordering of rule-based phonology and parallelism of OT. One of the problems of rule-based phonology was extrinsic ordering, which pauses a serious problem in learnability of the phonological grammar. One of the central tenets of standard OT is its parallelism, where candidates are evaluated in a parallel fashion. Parallel evaluation has seen difficulties in dealing with phonological phenomena where intermediate stages are indispensable for the analyses. There have been various proposals to incorporate serialism in OT, e. g. Sympathy Theory (McCarthy 1999), Stratal OT (Kiparsky 2000, 2001), OT-CC (McCarthy 2007), and Harmonic Serialism (McCarthy 2000, 2010). A commonality in these proposals is consideration of intermediate levels or forms between underlying and surface forms. NDP (Lee 2013) can be examined in this context. NDP departs from standard OT in that it keeps track of serial derivation. Ranked 'constraint pairs (C-pairs)' derive candidates in a serial manner. In doing so constraint ranking is regulated by a set of 'universal ranking principles' (URPs). The book shows how the NDP framework applies to morpho-phonological data from various languages, at the same time presenting each of URPs using abundant empirical evidence. NDP is established based on various data and problems that have been widely discussed in the literature, and shown its robustness dealing with serious problems that arise in parallel OT.