Sea-based economic processes rapidly expand, both in size and complexity. Many of the expanding activities in the North Sea, such as the production of offshore energy, are vital to the Dutch economy: they are part of the critical processes defined in the Dutch National Security Strategy. Inside the territorial sea, the zone between the coast and 12 miles out where national legislation applies, protecting these critical processes against malicious actors is a national responsibility. As offshore economic value creation surges, the organization of security within the 12-mile zone should be critically reviewed. But as vital activities move further out to the Exclusive Economic Zone (EEZ), a fundamental dilemma arises. Under the Law of the Sea, outside the 12-mile zone, the national mandate for prevention, detection, protection and response in the face of security risks and threats is limited. So how and by whom is the integrity of the – increasingly critical and vulnerable – processes and associated infrastructure in the North Sea guaranteed? Current policy documents hardly address that crucial question.