The fourth edition of this classic textbook has been revised to reflect recent developments in language teaching and learning yet retains the basic structure and approach so popular with its readers. Teaching and learning content has been updated, particularly taking into account the rise of task-based learning, Conversational Analysis and social models of second language acquisition, changes in national syllabuses and examinations and the increasing controversy over the role of the native speaker target. Each chapter has been revised to stand alone, enabling the text to be taught and studied out of sequence if preferred. A set of focussing questions has also been added to each and further reading sections have been updated. In addition, icons appear throughout the text signalling where extra information - summaries, data, lecture notes, test batteries and more - can be found on the author's accompanying website.