This special volume is concerned with the syntax of nonstandard varieties of (mainly British) English, and how such syntactic variation is accounted for within a range of theoretical models. There has been a growing interest in the modelling of dialect syntax (a) in a number of languages and (b) in a number of syntactic theories (see, for instance, the research on syntactic microvariation in some Germanic languages in Barbiers, Cornips & van der Kelij, 2002, or the construction-based approach to variation in Leino & Östman, 2005). We have brought together five articles written in different theoretical frameworks (Principles and Parameters, Stochastic Optimality Theory, Head-driven Phrase Structure Grammar, Word Grammar, and Construction Grammar), together with an introduction written by the editors, who themselves adopt very different theoretical frameworks.