The present invention relates to control of wind turbines based on predicted operational trajectories. A control system for a wind turbine is described where a main controller calculating one or more predicted operational trajectories and a safety controller validates at least one of the one or more predicted operational trajectories. The control system controls the wind turbine with the predicted control trajectory if the validation is valid, and controls the wind turbine with a safe-mode control trajectory if the validation is invalid. In an embodiment, the main controller is implemented as a receding horizon controller, e.g. in the form of a model predictive controller (MPC).