How will the volume of traffic develop over the coming years? What mode of transport will people prefer in the future? What needs to happen to improve people's mobility and make it more environment-friendly? If you want to design transport systems, you need to know the demand and the mix of users. Researchers at the DLR Institute of Transport Research have developed the model TAPAS (Travel and Activity Patterns Simulation) for this. TAPAS documents people's individual travel behaviour and shows the effect of changing conditions on infrastructure and transport policy. With the traffic model, researchers can calculate, for example, demand for transport or draw conclusions on transport development in the whole of Germany.