Violaine Delteil is Associate Professor at the Institute for European Studies, Paris University Sorbonne Nouvelle and member of the Research Centre ICEE (Integration and Cooperation in the European Space), France.Vassil Kirov, PhD (Sciences Po) is Associate Professor at the Institute for the Study of Societies and Knowledge, Bulgarian Academy of Sciences (ISSK-BAS) and Associate researcher at the Centre Pierre Naville, University of Evry and at the European Trade Union Institute (ETUI), Bulgaria.