Like the three-headed guardian of the underworld in Greek mythology, Cerberus will provide CO2 storage operators with a powerful gate-keeper tool for monitoring the fate of CO2 in the subsurface and detecting potential breach of containment early. Cerberus offers a solution that will i) facilitate cost-effective and site-specific monitoring strategies for geological CO2 storage projects, ii) enable efficient processing of large monitoring data sets and iii) reduce environmental and monetary risk by providing an automated containment verification and leak detection tool. The tool tackles the unmet need of having a high-definition multiphysics model from reservoir to surface, with strong prediction capabilities, and real-time, automated, low- cost analysis of monitoring datasets. It addresses the technology gap identified in the Green CCUS Roadmap “Towards a Fossil Free Future”. Cerberus have partners from Bifrost and the INNO-CCUS projects and will further liaise with and build on the knowledge from ongoing initiatives within open-source subsurface modelling and advanced machine learning. This will strengthen the connection of Danish CO2 storage research with international community. Cerberus will contribute to making geological CO2 storage in Danish reservoirs attractive for operators and affordable to customers. With a digitalised solution based on open-source software, Cerberus has potential for application in Denmark, the North Sea and globally.