All actors in the electricity industry are responsible for security of supply. That is to say electricity provision to the end-users, within agreed levels of continuity and quality. For years, each part of the energy supply chain - from resource extraction to generation, transmission, distribution, markets, and increasingly end use - has relied on using digital systems. The digital connectivity of electricity grids and digital trading platforms for electricity are experiencing considerable innovation. This text considers grid resilience and risks to energy and cyber security in our society.