Imagining, even before designing, new infrastructure for cities and territories involves increasingly broad thinking and involves increasingly articulated and connected skills. If, as Leonardo Cavalli points out in this issue's Overview dedicated to the time of cities, infrastructures last for centuries, serving people and buildings that last instead only decades, and digital tools, which of infrastructures regulate performance, evolve in years, or even months, vision and design are now key challenges for the future, even far into the future. Where won, they will not only ensure functionality, optimal service levels, and harmony with the environment at sustainable costs but will be crucial to the quality of life for citizens.

Why do we insist in the pages of DomusAir on the challenges that infrastructure design faces around the world, both where the population is growing at whirling rates and where it is declining, both where mistakes made need to be repaired and where they can still be avoided? The centrality in the life of cities and territories of infrastructure networks and the nodes that connect them is obvious and visible if we assess their role in the operation of services to people and businesses, transportation and logistics systems, energy production and distribution, and data management. But it is where the centrality of the functional role is less obvious and measurable that crucial games are played in the relationship that networks and nodes have with the city and the territory.

Not only functionality and service levels are central today, there are less tangible but qualifying aspects that define people's quality of life and the balance of the built environment. In order to understand and evaluate these aspects, it is necessary to step outside the perimeter of the strictly functionalist logic that the very nature of infrastructure promotes, often in distinct silos, be they transportation, energy, data, or more, and one must embrace the holistic view required by urban and regional planning, where alongside the performance of different services all people's needs must be listened to and corresponded to, asking what and how generates quality of life in the city and the territory.

First determinant is the accessibility, not only to central locations, that transportation infrastructure fosters for people and goods. The integration and coordination of access from long, medium and short distances plays a key role in the success of an area and often turns into the distinguishing factor for quality of life and economic competitiveness. The quality of local mobility, with the social and economic relations it fosters, is a crucial aspect in planning processes and too often are measured among the results achieved instead of calculated among the project objectives.

Geographical, cultural, religious identity is aspect that requires timely attention, respect and promotion. Iconographic, sometimes clumsy or picturesque recalls are not enough to ensure identity appeals in infrastructures that realize the most considerable public investments for a territory. A deep understanding of the nature of the territory itself and the layers of its history is necessary to outline possible evolutionary paths, in scenarios improved with the implementation of new infrastructure.

In the perspective of new construction, equity and inclusivity are key aspects: imbalances are the most dramatic issue of our time, a consequence of the lack of listening and assessing the impacts on the weakest. Investments with longer horizons, typical of infrastructure, must put equity and inclusiveness at the center to ensure qualifying returns in the urban environment. And balance again is needed for the relationship with the environment, a necessarily prevalent aspect in the development of plans and projects for infrastructure networks and nodes. There are no possible alibis for neglecting the environmental issue, which must be transferred from a compatibility check to a foundational element of the project.

The projects that DomusAir chooses look with increasing attention to the aspects described above, whether they involve the construction of new infrastructure and parts of cities, or contemplate the regeneration or upgrading of existing infrastructure and artifacts.

Opening image: Stuttgart Airport