Designed for beginning undergraduates studying for degrees in English, this textbook provides an introduction to a range of sociolinguistic theories and the insights they provide for a greater understanding of varieties of English, past and present. Drawing on both qualitative and quantitative approaches to sociolinguistic variation, the book provides a systematic overview of such topics as: *'English' as a social and as a linguistic concept *English speech communities *Social and regional dialectology in relation to varieties of English *English historical sociolinguistics, from Old English to late Modern English *Sociolinguistics and change in English *Outcomes of contact involving varieties of English *English and language planning *English, sociolinguistics and linguistic theory. The book contains data drawn from studies of English as it is used around the world. Throughout, there is an emphasis on facilitating a deeper understanding of linguistic variation in English and the social, political and cultural contexts in which speakers and writers of English operate.