This paper summarizes in a non-technical way what we know from empirical
studies based on firm-level data about the mutual links between international
activities of firms and productivity. It is written with a view to
inform policy makers in an evidence-based way. A special focus is on the
empirical evidence we have from studies using firm-level data from the
Nordic countries. It is argued that this empirical evidence does not provide
a sound basis for searching for similarities and differences (and their causes)
between the Nordic countries, and the empirical results reported cannot
qualify as stylized facts that can inform policy makers in an evidencebased
way.