This chapter deals with European cross-border issues concerning groups of companies. This chapter, after outlining the difficulties encountered throughout the world in defining and regulating the group, focuses on the specific policy choices endorsed by the EIR, which clearly does not lay down any form of substantive consolidation. Instead, the EIR, on the one hand, seems to permit the ‘one group—one COMI’ rule, even to a limited extent, and, on the other hand, provides for two different regulatory devices of procedural consolidation, one based on the duties of ‘cooperation and communication’ and the other on a system of ‘coordination’ to be set up between the many proceedings affecting companies belonging to the same group.