The systemic approach in studying tourism is firmly accepted in literature because of the complexity of the topic both from the supply side (the heterogeneity of goods and services making the tourist product) and the demand side (not every operator in the tourism network chain has a direct contact with tourists). To face this complexity the Input-Output analysis, theorized by Wassily Leontief, is widely used in the empirical studies regarding tourism. This methodology, however, gives just a snapshot, even very detailed in some cases, of the economic structure under study but gives very few insights from a dynamic point of view. To overcome this limitation the Dynamic Input-Output Model (DI-O model), implemented with system dynamics methodology, is introduced in this paper. Moreover some considerations about the technical sustainability of the production process are made possible by the proposed model.