We argue that, notwithstanding the importance of national industrial relations systems in shaping employment outcomes in situations of company restructuring, differences within countries also exist that cannot be explained by the influence of national institutions. Local union activity can affect corporate restructuring and influence how companies manage restructuring within the EU. The capacity of local unions to use company-based resources and the unions’ internal and external social relationships shape the variations in local union responses. In addition, our research suggests that the interplay of these factors in the socio-economic context of restructuring is crucial in explaining variations within countries. The article argues for the need to focus on these company-level developments as a crucial step in undertaking comparative industrial relations research.