RESili8 co-organized the 4th International Workshop on Electrical Power and Energy Systems Safety, Security and Resilience (EPESec 2023) held in conjunction with the 18th International Conference on Availability, Reliability and Security (ARES 2023). The workshop was aimed at collecting the most relevant ongoing research efforts in the digital security field for Electric Power and Energy Systems (EPES). It also served as a forum for relevant projects in order to disseminate their security-related results, boost cooperation, knowledge sharing and follow-up synergies, and foster the development of the EPES Security Community, composed of security experts and practitioners.