[1] The "Dresden Declaration" calls for people's mobility needs to be met in a cost-effective and environmental-friendly way[2] · .
[3] Then the proposed measures (whether they involve transport modes, the concept of "traffic avoidance, change of transport mode, technical improvements", the tautology of transport ecology or the "4 E", i.e. Enforcement, Education, Engineering, Economy/Encouragement) are scrutinised for transparency, fairness (polluters pay), unwanted side-effects and the application of the measure ("are there other examples of application elsewhere?
[4] The concept of « traffic avoidance, modal shift and technical improvements »[2] involves firstly reducing the volume of transport, then promoting intermodality and finally making technical improvements to vehicles and making the energy they consume sustainable.
[4] This means in fact implementing the Kaya identity applied to transport (see below).
Engineering is of a purely technical nature, whereas Economy/Encouragement re incentive systems, which may well be financial.
[4] As long as pollution is proportional to the distance travelled, Udo Becker defines tautology of transport ecology (in German « verkehrsökologische Tautologie ») as follows :[5] with : Demand can be decomposed according to:[5] with : Pollution can therefore be expressed as the sum of pollution according to the modes of transport : with : The general formulation takes on a more specific form when it comes to decarbonising transport, following Kaya identity.