A key challenge to understanding the eruption of globalization protest since the late 1990s is the lack of data on the protesters themselves. Although scholars have focused increasingly on these large protest events and the transnational social movements that play a role organizing them, information about the protesters remains scant. We address this research gap by analyzing survey data collected from a random sample of protesters at five globalization protests in three countries. By disaggregating protesters from the local area and protesters who traveled to the protest event, the role that organizations play becomes clear: SMOs mobilize non-local participants and coordinate travel to protest events. These data also suggest answers to the broader questions that have emerged about global civil society. In contrast to the expectations in recent scholarship, we find very few protesters came from outside of the countries in which the protests were taking place. Instead, we conclude that SMOs use the Internet to connect domestically grounded activists to transnational struggles and to mobilize them to participate in large-scale protest events. In other words, organizations do, indeed, matter in the globalization movement and have significantly expanded the protesting population beyond local citizens.