This chapter discusses past and present methods, theories and questions in the study of the phonology of English. The first section explores reasons why English phonology is relevant, both on a practical and social level as well as on a theoretical level. After a brief review of historical developments in the study of English phonology, the main part of the chapter discusses current trends and approaches, especially the use of acoustic phonetics to address phonological questions. Key areas of debate and future developments that are addressed include how both phonological research and language teaching deal with variation in varieties of English. The final section explores future developments, specifically, how technological change might influence research practices in English phonology and the viability of intelligibility as a goal in language teaching.