Driver assistance systems with simultaneous longitudinal and lateral guidance represent a major challenge due to their widely varying operating ranges in terms of vehicle speed, road adhesion utilization in longitudinal and lateral direction, and the degree of autonomy. Based on specific requirements for such functions, a successfully industrialized control approach is presented in detail that covers these operating ranges and all transitions in between them, i.e. also the activation and deactivation of functions. The basic idea of the approach is to divide the driving task into three levels: navigation, trajectory guidance and vehicle guidance and to develop the control architecture based on these three levels. Robust disturbance observers are used, which on the one hand reject external disturbances such as wind and road inclination and on the other hand are permeable for driver intervention if required. The chapter concludes with examples of driver assistance systems that have been developed for series production using this approach.