Forecasting involves the generation of scenarios that corresponds to a plausible future evolutions. A forecast is based on past data, and a theory implemented into a mathematic formulation, as opposed to a prediction, which is more subjective and based on instinct, or educated guess. Scenario building is one of the most widely used methods to undertake forecasting. MCRIT has developed forecast models to define consistent and realistic future scenarios for demography, economy, energy, transport, land-use and environmental impacts at all geographic scales, often in cooperation with specialists in the different sectors, applying very different software tools and theories, from Dynamic Systems and Complex Systems algorithms, to standard 4-steps transport models. Forecast models developed by MCRIT have been transferred to their clients and maintained for years, such as SIMCAT in the Regional Government of Catalonia, and SIMPORT, in the Port of Barcelona. MCRIT was also involved in TRANSTOOLS, for the European Commission, and HIGHTOOLS, a more strategic European forecast model.