Why do languages allow us to say 'the same thing' in so many different ways? One of the answers is that in saying what we want to say, we always position ourselves in social space as well, by speaking differently from relevant other social actors or groups. This volume explores how variability in language is exploited (and maintained) in order to perform this social identity work in interaction. It shows that variable features cluster together in socially meaningful ways when considered as social (communicative) styles linked to social identities.