This collection explores the essential skills and knowledge necessary for effective language teaching in times of rapid social and technological change, particularly within the context of European education. Addressing the complexities faced by both novice and experienced language teachers, the volume covers key areas such as multilingualism, assessment literacy, and the integration of digital tools in teacher education. It highlights the unique challenges of teaching in multilingual and multicultural environments and presents innovative approaches to teacher development. Aimed at teacher educators and trainers, as well as scholars and graduate students in the field, this book emphasizes the critical role of well-rounded teacher education in fostering competent teachers and confident learners. By drawing on historical perspectives and contemporary case studies, the volume provides new insights into the dynamic interplay between principles and practice in language teacher education, making it a valuable resource for those committed to a research-based language teacher education, responsive to current educational and social challenges.