On the fiftieth anniversary of the International Sociology of Sport Association and the International Review for the Sociology of Sport, the three guest editors for this special fiftieth anniversary issue of the IRSS, current ISSA president, Elizabeth CJ Pike, the immediate past president, Steven J Jackson, and current IRSS editor, Lawrence A Wenner, introduce the issue’s genesis and theme: ‘50@50: Assessing the trajectory and challenges of the sociology of sport’. In considering the trajectory of the sociology of sport, the ISSA and the IRSS, they reflect on the early development of the field and the founding of an international association and journal aimed at understanding sport in the social and cultural dynamic; they note early and ongoing challenges concerning the academic seating of the field, its legitimacy and impact, and its engagement with the public sphere and the ‘sociological imagination’. Speaking to the challenges of fashioning a special issue to represent the breadth of 50 years of the sociology of sport, the editors outline how a ‘50@50’ strategy was implemented to bring perspectives from 50 notable scholars and to ensure that a diversity of voices was heard, not only on a range of themes, theories and methods, but from diverse identities and locales. Addressing two overarching challenges – the global dominance of English as the lingua franca of scholarly discourse and the need to advance interdisciplinarity and engagement with scholars beyond the sociology of sport – will be key to broadening dialogue to help ensure the future sustainability and progress of the sociology of sport.