Welsh, like the other Celtic languages, is best-known amongst linguists for its verb-initial word order and its use of initial consonant mutations. However it has many more characteristics which are of interest to syntacticians. This is a concise and accessible overview of the major syntactic phenomena of Welsh. A broad variety of topics are covered, including finite and infinitival clauses, noun phrases, agreement and tense, word order, clause structure, dialect variation, and the language's historical Celtic background. Drawing on work carried out in both Principles and Parameters theory and Head-driven Phrase Structure Grammar, it takes contemporary colloquial Welsh as its starting point and draws contrasts with a range of literary and dialectal forms of the language, as well as earlier forms (Middle Welsh) were appropriate. An engaging guide to all that is interesting about Welsh syntax, this book will be welcomed by syntactic theorists, typologists, historical linguists and Celticists alike.