Twin-Control (http://twincontrol.eu/) is a novel concept for machine tool and machining process performance optimization. It combines several features in the field of ICTs in manufacturing towards a better performance of machine tools [1]. A holistic simulation model, a so-called Digital Twin [2] of the machine tool, integrating most important features of machine tools and machining process, is combined with monitoring and data management capabilities. Twin-Control will use a Digital Twin concept for the development of the simulation tool (Fig. 2.1). The Digital Twin is based on a combined application of the Cyber and Physical worlds, following the cyber-physical system (CPS) concept. The Cyber world consists in the computation, communication and control systems. The Physical world is composed by the natural and human-made systems governed by the laws of physics. A Digital Twin of the machine tool resulting from the combination of the different theoretical models that cover different aspects of the manufacturing process corresponds to the Cyber world, together with the cloud-based data management part,