Lov om kritiske enheders modstandsdygtighed, also known as the CER Act, is the Danish implementation of the EU's Directive on the Resilience of Critical Entities (Directive (EU) 2022/2557). The law, which entered into force on July 1, 2025, aims to strengthen the physical and operational resilience of entities providing essential services for vital societal functions. It mandates that designated critical entities in 11 key sectors—including energy, transport, health, digital infrastructure, and food—must conduct risk assessments and implement measures to prevent, manage, and recover from incidents that could cause significant disruptions. Key requirements include creating resilience plans, ensuring physical security, reporting significant incidents to authorities within 24 hours, and appointing a liaison officer. The law works in conjunction with the NIS2 directive, which covers the cybersecurity aspects, while the CER Act focuses on all other hazards, both natural and man-made.