A transport simulation and forecast model is presented, which is designed for the assessment of policy options aiming to achieve sustainability in transportation. Starting from a simulation of the economic behaviour of consumers and producers within a microeconomic optimisation framework and the resulting calculation of the modal split, the allocation of the vehicle stock into vintages and technological groups is modelled. In a third step, a technology-oriented algorithm, which incorporates the relevant state-of-the-art knowledge in Europe, calculates emissions of air Pollutants and greenhouse gases as well as appropriate indicators for traffic congestion, noise and road accidents. The paper outlines the methodology and the basic data sources used in connection with work done so far in Europe, presents the Outlook according to a 'reference case' run for the 15 current European Union Member States Lip to 2030, displays aggregate results from a number of alternative scenarios and outlines elements of future work. (c) 2004 Elsevier Ltd. All rights reserved.