As a fast, aggressive, contact sport there is the potential for women who play roller derby to challenge gender norms of passive heterosexuality and spectatorship. Played mostly by women, yet officiated mostly by men since its reinvention in the early 2000s, issues of gender are central to the sport, including its governance and management. Yet currently, the role of men in roller derby – as referees, coaches, and players – is unexplored. While the common conception of derby is that it inverts the gendered sporting dynamic – women as active participants and men in support roles – the reality is a complex interplay. This chapter examines the rise of sex integrated roller derby and what this means for both the experience of participants, and the future of the sport more broadly.