ATLANTIS goes beyond the scope of distinct assets, systems, and single CI, by addressing resilience at the systemic level against major natural hazards and complex attacks that could potentially disrupt vital functions of the society. The mission of ATLANTIS, which involves 39 European partners with complementary roles and skills, is to improve the resilience and the protection capabilities of interconnected ECI exposed to evolving systemic risks due to existing and emerging large-scale, combined, cyber-physical threats and hazards, guarantee the continuity of operations, while minimizing cascading effects in the infrastructure itself, the environment, other CIs, and the involved population, enabling public and private actors to meet current and emerging challenges by adopting sustainable security solutions.