The authors analyse the public systems supporting firms’ internationalization in Italy, France, Germany and the UK. They review the economic motivations underlying public intervention and the available empirical evidence, analysing the structure of National Promotional Systems in 2012. The major difficulties of their cross-country comparison lie in different institutional arrangements and degrees of transparency. These problems are circumvented using a common methodology for all countries and drawing from all publicly available information, websites and official reports they could find, as well as direct contacts with national and regional authorities. While public financial resources in the four countries are roughly similar, after controlling for the size of the economy and exports the German system stands out as the one with the lowest expenditure. Despite regulatory improvements, the Italian system remains complex, with some competences overlapping among institutional actors, and second to the UK in terms of transparency.