The field of English Language Teaching (ELT) that is categorized under applied linguistics is based on two major pillars: linguistics and psychology. The close interrelation of these two fields has constructed the route for ELT and the current know-how possessed by ELT researchers and practitioners has built upon the contributions of numerous outstanding linguists and psychologists. Accordingly, ELT holds a highly rich background that should be considered while discussing the latest developments in the field and designing a future projection. Today, our focus is mostly on the current trends in ELT like learner- and learningcentred approaches, meaningful learning, construction of knowledge, action- and processorientedness, communication and interaction, CEFR-oriented curricular implementations, plurilingualism and pluriculturalism, critical thinking, alternative assessment, learner autonomy, integration of technology, changing teacher roles, and professional development. Nevertheless, the great body of information on the methodological background in ELT cannot be ignored. The today and yesterday of ELT should be handled in an integrated manner. Under this framework, the basic motivation behind this comprehensive volume is our strong wish to introduce a thorough overview of the basic subjects in ELT in a single resource. The volume consists of 4 parts and 32 chapters. Part 1 introduces a methodological background in ELT and is devoted to the approaches and methods in the field. Part 2 is on teaching language skills including the main ones and sub-skills. Part 3 introduces issues on teacher education in ELT; and lastly, Part 4 covers various uncategorized further aspects in ELT.