This article reports on research which seeks to compare and measure the similarities between phonetic transcriptions in the analysis of relationships between varieties of English. It addresses the question of whether these varieties have been converging, diverging, or maintaining equilibrium as a result of endogenous and exogenous phonetic and phonological changes. We argue that it is only possible to identify such patterns of change by the simultaneous comparison of a wide range of varieties of a language across a data set that has not been specifically selected to highlight those changes that are believed to be important. Our analysis suggests that although there has been an obvious reduction in regional variation with the loss of traditional dialects of English and Scots, there has not been any significant convergence (or divergence) of regional accents of English in recent decades, despite the rapid spread of a number of features such as TH-fronting.