This edited volume seeks to highlight the effects of self-concept on L2 learning and teaching by considering a wide range of theories as well as their practical application. The book is divided into four sections and includes: chapters discussing various approaches related to self-concept; empirical studies related to the selves of the learners; research from teachers’ perspectives on students’ self-concept; and L2 motivational intervention studies associated with the development of self-concept of language learners. The volume contains a collection of studies from around the world (Central Europe, Canada, Asia and Australia) which were carried out using a variety of research methods and have a range of foci including adult and young learners, public and private education, foreign and second language settings, and teacher and learner motivation.