Synchronic variability in the area of phonetics, phonology, vocabulary, morphology and syntax is a natural feature of any language, including English. The existence of competing variants is in itself a fascinating phenomenon, but it is also a prerequisite for diachronic changes. This volume is a collection of studies which investigate variability from a contemporary and historical perspective, in both native and non-native varieties of English. The topics include Middle English spelling variation, lexical differences between Middle English dialects, Late Middle and Early Modern English forms of address, Middle English negation patterns, the English used by Polish immigrants living in London, lexical fixedness in native and non-native English used by Polish learners, and the phenomenon of phonetic imitation in Polish learners of English. The book should be of interest to anyone interested in English linguistics, especially English phonetics and phonology as well as history of English, historical dialectology and pragmatics.