Many transnational campaigns, and particularly the transnational campaign on violence against women, promote international norms that target the behavior of local non-state actors, while many of these local actors are subscribing to conflicting local norms. What happens when the international and local norms collide? When does transnational activism lead individuals and communities to abandon local norms and embrace international ones? In When Norms Collide, Karisa Cloward presents a theoretical framework for understanding the range of local-level responses to international norm promotion, and applies this framework to the issues of female genital mutilation (FGM) and early marriage. Cloward argues that, conditional on exposure to an international normative message, individuals can decide to change their attitudes, their actual behavior, and the public image they present to international and local audiences.She finds that the impact of transnational activism on individual decision-making substantially depends on the salience of the international and local norms to their respective proponents, as well as on community-level factors such as the density of NGO activity and the availability of an exit option from the local norm. She further finds that there are both social and temporal dimensions to the diffusion of international norms across individuals and through communities. Cloward evaluates the theory by examining changes in the patterns of FGM and early marriage among the Maasai and Samburu in Kenya, using a mixed-method empirical strategy that includes qualitative interviews and an original representative survey with a randomized experimental component.