The visible effects are the easiest to predict, the use of photo-montage and mock-ups can give an excellent idea of how the future infrastructure will appear and fit into the landscape. Of course the evaluation of the specific result will still be highly subjective. regards noise local pollution, the evaluation can As and be less subjective, but knowledge of the effects of environmental impacts is generally more to obtain. Many impact studies merely list the number of people who will be affected for example, those living within a certain distance from the infrastructure). This approach does perhaps provide a satisfactory image of the effects of the pollution moving through the space surrounding the infrastructure; however it is used primarily for noise, where the propagation of the noise is highly sensitive to the local geometry, and it is only through investigations at the construction stage that greater precision can be introduced and adequate measurements considered. This very often leads(in cities, at least to infrastructures being placed underground, for reasons of noise and appearance, much more for than reasons of local pollution. One wonders whether this situation can be improved and the effects of noise integrated in some more precise manner. To do this, one would have to be capable of improving the prediction of the effects, which could involve significantly improving the modelling capacity in these fields.