This book explores language teacher wellbeing across the career span from an ecological perspective. It reports on empirical findings from an extensive investigation into language teacher wellbeing across different career phases in various social, cultural and linguistic contexts. It is unique in casting light on the professional trajectory of language teachers across the career span and opening up discussions on the unique characteristics, psychological needs and strengths of language teachers at different points in their careers. It examines wellbeing in terms of the dynamic interplay between the challenges individuals encounter in their personal and professional lives, and the psychological, social and contextual resources that they draw on to buffer the impact of these challenges. The findings of the study will help readers to understand how language teachers can protect and nurture their wellbeing across each phase of their career, not only to remain in the profession, but also to thrive in the long-term. The book will be a valuable resource for anyone interested in the lives, wellbeing and psychology of language teachers in diverse contexts across the career span.