Abstract:An examination is carried out of the application of three soil erosion models, USLE/RUSLE, SLEMSA and the Morgan, Morgan and Finney method, to the Simeto catchment in Sicily, and of the differences in the results using the three models. The models are incorporated into a grid-based geographical information system, and the results are validated qualitatively and quantitatively. The significance of the choice of method to estimate the distributed input parameters and the method to validate the quality of the models are discussed.