The book argues that, in line with the latest research results and the author's educational experience, the existing, positive image of a second and foreign language (L2) teacher seems to be no longer valid. There is a strong need to dispel some of the commonly existing beliefs concerning the teaching profession by providing a thorough and multi-faceted account of issues connected with this field. This is in line with the assumption that shedding more light onto L2 educators' actual status is a great significance for creating a more realistic image of these educators who have to constantly cope with new and old challenges. Modern education systems in many countries are constantly evolving in the face of growing teacher shortages and low attractiveness of the profession. Therefore, there seems to be an urgent need to develop a better understanding of the well-being of teachers and its implications for L2 teaching and learning. This book presents a comprehensive conceptual framework to analyze teachers’ well-being and its influence on the quality of their professional performance. The book is of significance and relevance not only to L2 educators and L2 teacher trainers, but also to students and university graduates who are considering becoming teachers in the future. The content of the book is a valuable asset for policy makers who are interested in creating meaningful and efficient working conditions for those who are teachers and those who plan to become satisfied and motivated educators in the future.