In the wake of financial, sovereign debt and health crises, public interventions in the European economy have taken on a new level of breadth, marking a reentry in force of the state in economic life that goes beyond the regulatory state. Yet, these interventions do not follow the old Keynesian interventions neither, being shaped through a particular logic of investment that link public and private actors in a particular configuration. The introduction to this special issue lays out this configuration for the case of the EU and its Member States through the concept of “European Investor state.” By this concept, we refer to the redefinition of the role of European states in the economy as an “investor,” in reference to private investment funds, which the state seeks both to imitate and to enroll. The paper embeds this redefinition of state intervention in the context of the 2010s in Europe, characterized by worries about “secular stagnation” and growing concern about an “investment gap,” interpreted as the failure of financial markets to invest in productive sectors, especially when risky. The budgetary constraints and the ideological outlook then shaped the specific financial and off-balanced sheet tools of the investor state. Finally, the paper explores the implications of the Covid-crisis on this intervention model. It concludes that despite major changes in fiscal policy at the EU level, this approach is likely to persist, because of the lasting interpretation in terms of “investment gap,” which only public-private collaborations are seen to be able to fill.