Population ageing and shrinking are demographic phenomena with far-reaching implications for sustainability in the current context of extensive and rapid urbanization. This Perspective rationalizes their interface by (a) identifying the challenges and opportunities that ageing and shrinking urban populations will have for implementing the sustainable development goals (SDGs), and (b) discussing some emerging interventions to capitalise on the opportunities and reduce the challenges to achieving sustainability. We argue that a diverse set of context-specific technological, socioeconomic, institutional and governance interventions would be needed to leverage effectively the opportunities and minimize the risks posed by ageing and shrinking urban populations for long-term sustainability.

Drawing on examples from the Nordic countries, this article aims to explore the practical application of strategic policy and planning instruments and approaches that facilitate the integration of land use and transport planning and promote sustainable policy measures through collaboration among stakeholders across various governance levels. This research applies a qualitative research design including literature research, interviews, and workshops involving practitioners from the five Nordic countries. In this paper, we present an overview of the planning structure in the Nordic countries, including institutions that govern land use and transport planning. We identify different approaches to bridge the gap between land use and transport planning, such as the Finger Plan in Denmark, MAL in Finland, Concept Studies in Norway, and Strategic Choice of Measures in Sweden. Many of the examples employ informal collaborative approaches among authorities to form a shared vision and seek consensus on a combination of policy measures and actions. The paper examines collaborative approaches in relation to regulatory planning and discusses the role of these processes in advancing integrated land use and transport planning and fostering sustainable urban development.

The Strategic Choice of Measures (SCM) approach aims to integrate different perspectives and identify measures to adapt new infrastructure projects to their local context at an early stage of Swedish transport planning. SCM is a loosely structured framework for collaboration between actors from, e.g., municipalities and the Swedish Transport Administration, in order to facilitate the coordination of transport planning and land use planning. This paper aims to explore the consideration of environmental aspects in early-stage transport planning by analyzing the SCM approach. An explorative research approach is applied based on literature studies, semi-structured interviews, and a focus group interview. The result shows that in the SCM process, environmental aspects such as noise and air pollution generated by road traffic in urban areas, engage the actors, whereas aspects related to landscape and water were perceived as poorly addressed and received less attention. The consideration of environmental aspects in the SCM process is affected by the local and national authorities’ different interests and the competences involved. To consolidate environmental aspects in early transport planning, these aspects need to be explicitly addressed in the SCM guidelines and the link between the SCM and preceding and following planning stages needs to be strengthened.

Sustainable development of the transport system increasingly requires integration of land-use and transport planning practices. To identify and implement measures that maximize synergies between transport, land-use and environmental issues are essential to achieve sustainable outcomes of transport planning. The strategic choice of measures (SCM) approach, applied in early-stage planning of transport infrastructure projects in Sweden, constitutes a platform for collaboration between transport and land-use authorities for better coordination of the different practices in a specific context. This paper aims to analyze SCM processes from a systems perspective to illuminate consequences of system boundaries on how environmental aspects are considered and what aspects are included or excluded. A case study approach is applied, based on observations and document studies of two cases in Stockholm region. The result shows that coordination of transport and land-use planning practice in the SCM process, implies handling of conflicting views of development in the project area. In order to create shared objectives and visions, constructive dialogue and collaboration are two key features. Moreover, it is a challenge to handle all the different problems and measures in the SCM. It is essential to understand synergies as well as how problems and measures in different planning processes relate to each other. A systems perspective as a support when analyzing problems in an SCM can enable the detection of links between transport, land-use and environmental problems. The systems perspective could contribute to the identification of measures with synergetic effects and subsequently the implementation of multi-functional solutions.