Teaching by Principles: An Interactive Approach to Language Pedagogy is a widely acclaimed methodology text used in language teacher education programs around the world. In this fourth edition, Dr. H. Douglas Brown and Dr. Heekyeong Lee offer a comprehensive survey of practical language teaching options firmly anchored in current research on second language acquisition and pedagogy. This book features a comprehensive update on current issues, new research findings, and innovative classroom teaching techniques, with additional and reworked chapters to reflect this information. It includes a description and analysis of new foundational principles such as agency, identity, languaculture, communities of practice, embodied cognition, and self-regulation. Each chapter begins with pre-reading organizers, and the book is filled with frequent statistics and pedagogical “tips.” Numerous “classroom connections” are provided to stimulate practical applications of concepts and principles. End-of-chapter group activities, discussion topics, and suggested additional readings further enhance the learning experience.