The report deals with the pollution load from the transport sector in cities. The pollution problems are to be complex and complicated. The approach in this project is to work out a theoretical and methodical framework in order to secure that the different measures to transport are to be compared and evaluated in a way of consistency. Different decision models are developed for systematizing the base of decision. Such types of models and methods for estimating the environment, are discussed and compared. The pollution load in cities and the effects of different measures, are described. A proposal in systematizing the decision base for practical use, is presented. The discussions are related to the theoretical works and real analyses being executed in Norway and internationally. 70 refs., 5 figs., 3 tabs.