Book excerpt: Action sports have undergone dramatic growth, commercialization, and institutionalization over recent decades. This book uncovers the social, political, economic and organizational dynamics of their professionalization. After sketching some of the main transformations at stake in the field, the contributors provide novel insights into the changing structures in the action sports industry and the effects on athletes, coaches, agents and the cultures more broadly. Such trends came to the fore in the inclusion of surfing, skateboarding, sport climbing and BMX freestyle into the Tokyo Olympic Games. The book explores the working lives of action sports athletes, more specifically when it comes to their social media practices and the commercial pressure emerging from sponsors, and it also provides key insights into the institutionalization and professionalization of action sports amid ongoing processes of globalization, commodification and incorporation. Overall, the book reveals how different action sports (i.e., snowboarding, surfing, kiteboarding, parkour, climbing, skateboarding), and across countries, are at various stages in the professionalization process, with local, national and international responses and reactions to such trends differing considerably. The chapters in this book were originally published as a special issue of Sport in Society.