European-level government presents new opportunities and constraints for domestic social actors. But barriers remain to contentious action in the transnational realm. Most individuals have difficulty ascribing the sources of their grievances to the EU, transaction costs impede their efforts to co-ordinate collective action across national boundaries, and traditional routines of collective action attach citizens to their national systems. Nevertheless, some actors are able to mobilise at the European level. Using reports from Reuters, the study finds that most protests are made by occupational groups, such as farmers or workers, with little mobilisation of non-occupational groups (such as environmental or women's NGOs). Also, 234rather than a direct displacement of contentious politics to the supranational level, one sees a range of mobilising styles: transnational co-operation against domestic actors, collective European protests, and the domestication of European issues within national politics. The authors speculate that these outcomes will allow the EU Commission to keep such protests at a distance, and that activists whose careers are in Brussels-based NGOs will be deprived of the weapons they need to back up their claims.