Sex and gender are interconnected, conflated, different, and complex. Arguably, there is no cultural arena more affected by the complexity of sex/gender than sport, where the presumed need for a male/female binary is personalized, medicalized, and politicized. Gender Defenders of the Sport Binary considers how medical, policy, and media discourses shape understanding of nonbinary athletes, and more broadly cultural understandings of gender as chosen and sex as biologically measurable. Tracing discourse across more than 100 years of media coverage, decades of medical debate, and overlapping sport regulatory policies, this book considers how the force of cisgender ideology creates a singular narrative centered on fairness that dominates transgender and intersex women and erases them from elite sport. This book traces the influence of powerful contexts such as language and masculinity in constructing boundaries around who can and cannot fit in women's sport. "In Gender Defenders of the Sport Binary, Bell and Osborne offer a compelling and incisive critique of how sport, medicine, and the media converge to police gender under the guise of fairness. In a time of global debates on gender and athleticism, this thought-provoking book unpacks the exclusionary frameworks that elite sport uses to marginalize transgender and intersex athletes, revealing the deep entanglements between gender ideology and power. Using meticulous research and sharp analysis, the authors challenge us to reconsider the boundaries of inclusion, presenting a vital call to reimagine sport as a space where diversity is not disciplined, but celebrated." -Anna Baeth, Ph.D., Director of Research, Athlete Ally