An in-depth analysis of Breton using a modular framework for phonology What is the relationship between phonetics and phonology? Are phonological features innate and universal, and do they have fixed phonetic correlates? These questions have recently received renewed prominence in theoretical debates, and this book explores them from a modular, substance-free perspective. This in-depth analysis of Breton serves not only to introduce previously underused data into the theoretical landscape but also to demonstrate the viability of a modular framework for phonology. The book introduces a minimalist system of phonological representations built up on a language-specific basis, without regard to the phonetic realisation of phonological objects, and integrates it with a fully-fledged computational framework and a stratal interface between phonology and morphosyntax, showcasing the numerous empirical and conceptual advantages of a substance free view of phonology. Presenting the first comprehensive analyses of the sound patterns of a Breton variety treated in a substance-free phonological framework, this book will enhance the understanding of Celtic phonology and offers a valuable reference for postgraduate students, academics and researchers working in phonological theory and Celtic studies. Key Features Presents an in-depth treatment of Breton phonology in a generative framework, focusing on traditional varieties rather than the standardised written language (unlike most theoretical work to date) Introduces previously underused data into the theoretical landscape Re-establishes the value of non-trivial phonological representations after a period of theoretical neglect and at a time when formal phonological theory is under pressure to accommodate new empirical findings from variationist and laboratory approaches.