Recent decades have witnessed a growing number of global campaigns on girls' and women's education, including major global policy initiatives such as the MDGs and the SDGs. While scholars have critically analysed the conceptualisations of gender, equality and development in such campaigns, and their significance for national level policy and practice, less has been written about why and how girls' education came to be such a high profile feature of international policy frameworks. This paper draws on perspectives from transnational social movement theory, which has been used by gender scholars to explore the activities and significance of non-governmental organisations for agenda-setting at the global level. In this paper these perspectives are applied to the field of global education policy, through an analysis of evidence from international conferences, data on aid flows and interviews with key policy actors, to explore the factors behind rise of the global agenda on gender equality in education. In doing so, it suggests that the current dominant framing around girls' education, access and quality, may be explained by the relatively weak involvement of non-governmental women's groups in proportion to the strong involvement of multilaterals, bilateral agencies, national governments and more recently, private sector organisations.