While considerable theoretical attention has been paid to the origins and substance of the international women’s human rights regime in recent years, surprisingly little attention has been paid to the effectiveness of this regime. Feminist international legal scholars have examined the international law-making process in detail and highlighted conceptual and substantive deficiencies in the women’s human rights regime but they have tended to neglect the significance of this regime for state behavioural change. This neglect raises several important questions: what are the implications of the regime regarding international norms of sexual nondiscrimination for state legislation and public policies? Under what conditions do international norms of sexual non-discrimination diffuse or fail to diffuse into states? Why do certain norms diffuse more readily than others? Through what processes, promoted by which agents, do states come under pressure to incorporate international norms of sexual nondiscrimination? In short, to what extent do international norms of sexual non-discrimination matter?