In this paper we present a system to robustly estimate the 3D position of a human head. Before the face model is positioned in the initial frame, it is adapted to the 3D scan of the tracked human head. Head tracking is achieved by minimizing a robust cost function with a stochastic optimization algorithm called Differential Evolution. This approach enables the estimation of large motions between consecutive frames. Furthermore, the algorithm can even handle a large number of outliers e.g. caused by occlusion and still estimate the precise position.