The growing use of digital technology in the nuclear field has heightened security concerns around the protection of radioactive materials. This publication offers practical strategies for implementing robust information and computer security measures and it underscores the importance of a tailored, graded approach to meet the specific needs of various facilities and organizations. By presenting the latest best practices and risk mitigation strategies, this publication equips stakeholders with the necessary tools to fortify their digital defences and safeguard radioactive material and associated facilities.