This introduction poses the basic question that this book attempts to answer: How did an eighteenth-century Scots song, the words of which not even most Scots fully understand, become one of the most well-known songs in the world? This book argues that to answer this question, we need to investigate the social practices that have emerged around the song, and not just its distribution through media such as print, broadcasting and recording: these practices are, in particular, its use as a song of parting, as a song of New Year, and the tradition of singing it in a circle with joined, crossed hands. The introduction also outlines the approach taken to referencing and bibliography in this book, and acknowledges the significant support the author received in researching, writing and publishing it.