Periodic Report Summary 2 - IBIAS (Understanding contemporary interest group politics: mobilization and strategies in multi-layered systems) iBias addresses an unsettled political science problem, namely: How does the shifting of policymaking competencies to higher levels of government affect the opportunities of societal interests to seek representation? On this issue two different theoretical expectations exist. On the one hand, the Madisonian view entails that shifting competencies upwards is a healthy antidote to the powers of specific interests that may dominate smaller polities. Multi-levelness may also provide political opportunities as it enables actors to make strategic venue shifts when they are unable to attract the necessary attention at one level. On the other hand, shifting policymaking upwards may seriously restrict the opportunities for diffuse interests, undermine encompassing forms of interest representation, and increase the barriers for local groups to gain attention. Instead of creating opportunities for all, multi-layered systems may decrease opportunities and reproduce or reinforce representational bias. One of the reasons why the implications of multi-layeredness are poorly understood is the fact that political science has not developed a proper understanding of what representational bias means. Some scholars see bias in terms of mobilization, others understand it in terms of access or influence, while still others conceive it in terms of the strategic interactions between organized interests and policymakers Moreover, little research has been conducted on how institutional variation and complexity may affect representational bias. iBias integrates theoretically, methodologically and empirically various aspects of group politics and takes explicitly into account the institutional complexity organized interest are confronted with. Its approach lies in the theoretical combination of mapping interest group community dynamics, with a more nuanced characterization of organizational form and an in-depth investigation of bias in terms of strategies. This innovative mixed-methods research methodology allows us to demonstrate that resource dependencies to one level of government shape advocacy behavior towards other levels of government. Hence, institutional interlocks have tangible effects on patterns of interest intermediation. Another important finding is the disconnection between the public agenda (policy priorities among the broader public) and the system of interest representation. The general optimistic expectation regarding the role of interest groups as intermediaries of societal interests receives little support in the iBias findings so far. For instance, policy areas that EU citizens find most problematic for their countries do not seem to be systematically addressed by interest groups and EU policymakers. Such findings raise questions about the democratic accountability of our political systems and encourage further reflection on how to improve them.