The EU’s basic objective is to create a single European market as a tool for political integration. This objective is being transposed into all economically strategic sectors, including at a data level in each of these sectors. In the infrastructures, this objective translates into the unbundling of the network industries into a monopolistic infrastructure on the one hand and a market for services delivered on the basis of these infrastructures on the other. In this special issue we look at energy, rail and air EU-wide infrastructures, how they have developed, whether they make progress, and what obstacles they encounter.