In the framework of the ESTEEM Project co-financed by the European Commission, an urban dispersion model (ADMS) has been applied for two sites in Rome with high topographic and traffic regimes complexity, where two air pollution monitoring stations are located. The traffic emissions values have been provided by TEE (Traffic Emissions and Energy) model developed at ENEA and based on a 'correction' of emissions calculated from average speed with a 'Kinematics Correction Factor' (KCF) which represents the speed variability along the link. This factor is derived as a function of link length, traffic density, link average speed and green time percentage at the traffic light. Hourly averaged CO concentrations have been calculated applying the ADMS model for the selected sites. The simulations were done using the meteorological conditions of 'real' days representative of the standard level of pollution in the season at the two sites, and compared with the measured pollution data.