The goal of this document is the definition of the MOEEBIUS Common Information Model (CIM), which will describe the high level domain model comprising the basic elements (semantic concepts, events, relations, interfaces, etc.) and will support the information needs of the components underlying the MOEEBIUS project. The document builds upon the business scenario for a holistic and dynamic modelling and simulation / optimization approach that enables (1) Improved predictions on the basis of more accurate and dynamically updated Building Energy Performance Simulation (BEPS) models, (2) Real-time building and district performance optimization through control and predictive maintenance and (3) Optimized retrofitting decision making on the basis of improved performance predictions. Taking the holistic scenario as reference, the document further elaborates on the data exchange requirements envisaged for each of the components. In this regard, connections to the relevant sections in the building industry reference data models are provided.