The European Union (EU) increasingly resorts to new forms of governance to establish unified health and welfare policies without member states having to transfer their sovereignty to a supranational level. European Administrative Networks are important instruments in the toolbox of new forms of governance, dealing with rulemaking, rule monitoring, and rule enforcement. Operating beyond, but not above, the state, European networks of national administrative units allow for interaction and exchange to coordinate national responses to increased interaction across their borders. The authors use social network analysis to uncover the pattern of interaction among national representatives in two central EU health care networks. Their analysis finds not only that the network in the area of pharmacovigilance has more competences, resources, and capacity to improve the enforcement of EU rules than the network regarding cross-border health care but also that the driving forces behind network interaction appear to differ quite a bit as well. While the supranational character becomes apparent in the former network, network interactions in the latter seem aimed at mitigating the impact of patient mobility rather than improving cross-border health care take up. Copyright © 2021 by Duke University Press.