This chapter addresses two issues related to tracking people through mobile technologies and spatial planning decisions. The first major part deals with the question of how knowledge developed through the use of new tracking technologies can impact the spatial planning process. We argue that global positioning system (GPS) data are valuable – if not vital – for the improvement of travel demand forecasts by means of an activity-based transportation model when assessing travel demand management (TDM) policies such as spatial planning strategies.
Based on a brief historical outline with regard to planning policies and an overview of various travel demand models, the need for advanced data and their use in modelling practice is shown. In the next section, the other topic of this chapter discusses what kind of spatial interventions can be expected due to the use of new tracking technologies. Here, four application areas related to travel demand modelling are identified and subsequently explained: the use of route knowledge and the concepts of accessibility, activity spaces and mental maps.