SUMMARY
Digital Terrain Models are being used for planning and hydrological applications,but also for visualization and many other tasks. For all applications, it is necessaryto know the model quality, because it has an impact on the quality of the decisionsthat are drawn from the terrain model applications. In this paper we present amethod that is suitable for comparing two terrain models to each other. Vertical, butalso horizontal displacement of terrain features can be found automatically, whichare systematic errors and are in the main focus of this paper. However, randomerrors can be quantified, too. This method allows establishing a vector field ofdifferences between two models, measuring the deviation from one to the other.These deviations are a measure of quality of one model against the other. Emphasiswill be put on comparing terrain model from NASAs Shuttle Radar TopographicMission to terrain models of known quality in Brazil.