The Predict-Er brings a multidisciplinary approach that combines, for the first time, nuclear, analytical, statistical, and remote sensing techniques to develop a novel tool capable of predicting changes in soil erosion rates and sediment dynamics over a range of management scenarios. The representation and process models integrated into the Web-GIS user-friendly tool aim to support decision-makers in targeting appropriate conservation measures to minimize on-site and off-site effects of soil erosion. The relevant stakeholders' feedback is used to improve the tool design and performance. The best prediction models will be proposed to optimize the quantity of input data for model parameterization in future applications across different regions. Using the decision-making approach invented by Predict-Er will substantially impact the soil and surface water quality with consequent socio-economic benefits and impact on national and international policies.