For over half a century, the study and planning of traffic and mobility have recognized the characteristics of settlements as a determining role in the generation of displacements.
No longer read as a simple relationship between flow and capacity, traffic is considered as the result of the need to move from one place to another to reach the locations of the activities to be carried out.
It follows that settlements structured and organized differently will lead to different movements. There are numerous assumptions and beliefs in this regard, including, for example, the idea that high-density settlements with mixed land uses determine variations in the demand for mobility, reducing car travel and increasing walking and cycling
The rich quantitative literature on the subject, however, attests the groundlessness of this type of assumption, revealing the complexity of the phenomenon. Intuitive considerations in this regard thus prove to be anything but founded, raising far-reaching issues and problems.
The idea of the need for a greater relationship between transport and land uses, now recognized both in academia and in common opinion, is in fact based on these considerations.
Understanding the phenomenon that binds the characteristics of settlements and the demand for mobility is therefore an essential requirement for good planning, be it for the city or for mobility, assuming that both are aimed at improving the quality of life.
Thanks to the prevalence of attention on these issues in the field of transport engineering, the approach to the topic is often strongly sectorial and technocratic, also characterized by a strong resistance to change. The latter, as well as the deliberate assumption of a narrow perspective on the topic, is motivated by the need to develop analytical descriptions (using algebraic formulas) of reality, which can be inserted in mathematical simulation models which constitute the main tools to support decision making in planning. mobility.
Broader perspectives or theories closer to reality but less easily translatable into mathematical formulas are not very successful, while the adoption of theories and assumptions whose distance from reality is now widely recognized remains.
From the analysis of attempts to conceptualize the phenomenon, however, traces of an evolution of theoretical reflection emerge, which attest to a growing focus on cognitive and decision-making processes, as well as the broadening of the context in which mobility is placed. This is linked to the actual difficulty, if not impossibility, of schematic representation of this complex phenomenon, the study of which is - and must be - multidisciplinary.
In recognizing this characteristic, and the relative inadequacy of rigidly sectorial or sectorially integrated approaches, it is necessary to know how to read the phenomenon from several points of view. In this perspective, the volume offers a framework of the theme with particular attention to theoretical reflection, filling a void that interests both international literature and, if not above all, Italian literature and manuals on the subject.
