This research is being carried out for Environment Canada and seeks to provide emissions estimates associated with all metropolitan road links in the CMAs covered. An Integrated Urban Modelling Framework is used where trips originating from and arriving in each small census area are estimated for each hour of the day. These trips are assigned to the road network using an advanced assignment algorithm and an appropriate environmental module is employed to estimate emissions associated with the traffic levels on each road link. Something similar is done for light, medium and heavy commercial vehicles and public transit vehicles. Variations by day and by month are taken into account to provide a complete picture for a full year.