Have you ever noticed an accent or puzzled over a dialect phrase? Language can be a powerful tool with which one can create a persona; it can be a common ground between people or can be used as a divide between social groups. This Companion is for anyone who is interested in how and why people speak and write with such diversity. The Routledge Companion to Sociolinguistics includes articles by leading scholars in the field on methods of observation and analysis; social correlates; socio-psychological factors; socio-political factors; and language change. With a substantial A-Z glossary of key terms and concepts, directions for further study, and detailed cross-referencing with links to the glossary, The Routledge Companion to Sociolinguistics is both an essential broad-based introduction for those new to the field, and a highly useful reference for the more advanced linguist.