Civil society organizations in Western societies are widely reported to have significant political power. Policy makers increasingly emphasize the important role of such organizations as “equal players” in the political process, while outside institutional politics, civic advocacy recently regained attention through the rise of global and transnational social movements. This paper draws attention away from individual engagement in social movements and from single non-governmental organizations (NGOs), toward inter-organizational networks of civil organizations and their role in public policy processes. Taking an inter-organizational perspective on civic advocacy, the paper starts with a theoretical reflection on two bodies of literature: social movement theory, and the literature on inter-organizational networks. The combination of insights from these two areas builds the theoretical background for analysing the “network effect” for joint advocacy by civil organizations in networks. The network effect, as discussed here, builds on a set of propositions about how organizing in networks affects the network members themselves, as well as how networks change the role of civic action in the policy process. These propositions are presented and discussed from two different angles: inside and outside networks