This groundbreaking volume delves into a diverse selection of trans-themed children's and adolescent literature published over the past 25 years, spanning everything from picturebooks to young adult novels. These stories, often at the centre of heated debates, have sparked both widespread acclaim and fierce backlash. Through a critical lens, this volume examines how these works challenge - or, at times, reinforce - traditional notions of gender. By contextualising each text within its cultural and social moment, the analysis highlights the development of narrative and didactic approaches, drawing attention to the fraught terrains of representation and allyship. With recurring themes of identity, inclusion and controversy, this volume unpacks the complex dynamics between narrative intent and reader response, revealing the tensions and possibilities within this emerging field. It argues for the importance of integrating trans-themed fiction into the broader study of children's literature, not as a niche category, but as a necessary part of the canon. By employing a range of critical tools and methodologies, this work situates trans-themed literature within its contemporary context, offering fresh insights into its cultural impact and reception.