This book is a research monograph divided into two parts. The first part describes the methods used to build the first sizeable corpus of informal conversational data collected from bilingual speakers of Welsh and English: Siarad. The second part describes the linguistic analysis of data from this corpus (available at bangortalk.org.uk). The information in Part One will be useful as a `how to' manual on building a bilingual spoken corpus, including methods of data collection, transcription, glossing and analysis. The findings reported in Part Two throw new light on the debate regarding...