In order to optimise the dynamic properties of commercial vehicles, a programme system of particular flexibility has been developed. For model formation, the system is largely similar to FE programmes. The vehicle model is built up of individual modules based on the input data. In the case of components for which the data is difficult to ascertain by computer, experimental performance maps can be used. In terms of kinematics and physics, the programme is non-linear. Following an explanation of the theoretical basis, three examples of simulation from the fields of handling and vehicle dynamics are shown and compared with test results.