This chapter addresses the technological megashift and implications for security and accountability within the EU. Digitalised interconnectivity of increasingly ‘embedded’ systems, infrastructures and societal functions are megashift features. Although the EU hardly lacks technological strategies, accountability structures beg improvement, and there are multiple expert groups with insufficient coordination and societal focus. The EU suffers from techno-optimism—coupled to powerful objectives of fuelling economic growth—which can lead to broadly conceived and represented security issues falling in shadow and struggles between interests being inadequately addressed. This chapter analyses how the EU deals with the megashift with respect to threats, surveillance systems, infrastructural vulnerability and public-private accountability. It is suggested that the EU take (i) a holistic grip on the megashift and implications, (ii) abandon optimistic techno-determinism for nuanced and contextual understanding and (iii) avoid outsourcing management of sensitive data and critical infrastructures.