The EU is suffering from a democratic deficit and many voices insist on the need to bridge the gap between Brussels and the European citizens. Brussels-based civil society network organizations are thought to help narrow this gap and further reduce political inequality. These organizations are the last link in the communication chain between citizens and the EU: between civil society organizations (CSOs) and EU structures. These meta-CSOs (i.e. networks of and for CSO networks) stand at the core of the developing transnational civil society. This paper investigates how contextual and organizational factors impact upon configurations of networked CSOs at the EU level and how, in turn, this influences their capacity to bridge the gap between the EU and its citizens. The results reflect the crucial trade-off between external effectiveness (output function) and internal representation (input functions), which can undermine the potential of CSOs to influence the democratic public sphere at the EU level. Particularly, the project systematically explores membership, funding resources, institutional and policy opportunities along with networking factors (type, shape, ties) within several cases of transnational CSO networks operating in Brussels. The cases are selected across policy sectors, comprehensively covering the civil society space in the EU. In addition to contextual and organizational aspects, the focus on relational factors, with the help of social network analysis based on survey data, will expose patterns emerging from the transnational civil society space and its potential for defining the EU-citizens relationship.