We are celebrating the 30 years of the EU internal market. The internal market process also led to the development and integration of energy markets in Europe delivering millions or billions of euros in annual benefits. By pooling our resources, we increased our resilience against energy shocks, but we also increased our interdependencies. In the next decades, billions or trillions will be invested to live up to the ambitious decarbonization targets of the EU Green Deal and the Fit-for-55 package. To what extent will Member States continue to rely on energy markets to guide these investments? Will we increase cooperation across borders or favor local solutions? How can we avoid that EU Member States voluntarily or involuntarily free-ride our shared energy security at the expense of others?