The EUROpean SAlt marshes Modelling (EUROSAM) project is part of the Thematic Network European Land-Ocean Interaction Studies programme. The main aims of the EUROSAM project were to fill in some of the main gaps in the understanding of ecological processes, to integrate this knowledge into models to predict the likely response of salt marsh ecosystems to environmental changes, and to make the knowledge available to decision-makers. Research work and model development for the project were carried out by researchers in France, Portugal, the Netherlands, and England, and included studies on sediment dynamics and interactions with vegetation, plant population dynamics and genetics, models of organic matter production and cycling, studies of animal communities, food webs and organic matter fluxes, and development of hydrodynamic models at different scales: salt marsh, bay, and estuary. This paper describes the main aims and outputs of the EUROSAM project, and the incorporation of the findings and models into a prototype Decision Support System (DSS). The EUROSAM DSS is designed as a guide for the non-specialist to understand the important role and functioning of salt marshes, and for use as a management tool. Example scenarios were selected from the work within the project to illustrate the interactions between components of the salt marsh-mudflat ecosystem, and the potential impact of human activities and environmental change on the salt marsh system.