In Foreign and Second Language Learning, William Littlewood surveys recent research into how people acquire languages and considers its relevance for language teaching. He describes the most important studies and ideas about first language acquisition, and how these have influenced and developed into studies of second language acquisition. He considers the background of language theories which were current before the present interest in acquisition research, and looks at factors such as learners’ errors, whether learners are predisposed to acquire language in certain sequences, why some people are apparently more successful at learning languages than others, and how learners make use of their new language to communicate. The use of clear examples, the careful explanation and balanced commentary on the research enable the reader to evaluate the evidence and consider the relevance of work in this field to the day to day concerns of teaching and learning languages.