This talk aims to provide a general view of the background and current state of building performance simulation, which has the potential to deliver, directly or indirectly, substantial benefits to building stakeholders and to the environment. However the building simulation community faces many challenges for the future. Several challenges relate to the need to provide better design support. Issues include early phase design support, multi-scale approaches (from construction detail to district level), uncertainty and sensitivity analysis, robustness analysis (employing use and environmental change scenarios), optimization under uncertainty, inverse approach (to address “how to” instead of being able to answer “what if” questions), multi-physics (particularly inclusion of electrical power flow modeling), and integration in the construction process (using building information modeling (BIM), process modeling, etc). Another group of challenges relates to the need to provide support for building operation and management. The issues here include accurate in-use energy consumption prediction and model predictive control. The presentation will highlight current research in these areas in Eindhoven.