<p>The ramms:: debris flow model has been developed to simulate the flow of debris flow in complex terrain. The model is used for debris flow hazard analysis in Switzerland and around the world and helps design mitigation measures. It combines state-of-the-art digital solutions with useful input features and user-friendly visualization tools. Many input and output characteristics have been optimized to enable engineers and geoscientists to define event scenarios, evaluate simulation results, and predict the impact of proposed structural mitigation measures on debris flows. The second-order numerical solution of the shallow water equation is the effective solution of the particle motion equation. The height and velocity of the flow are calculated on the 3D digital terrain model. Maps and remote sensing images can be superimposed on terrain models to help standardize input conditions and facilitate the calibration of models with historical event data. </p>