Sustainability and sustainable development have been on the global agenda since the 1980s, and the UN Sustainable Development Goals have guided international action since 2015. This Themed Issue is devoted to Sustainable Transport because society is now at the stage where sustainability is no longer an abstract goal that is relevant to only certain projects but is a mainstream requirement that municipal engineers must incorporate into their day-to-day work. Such practice requires engineers to apply frameworks and tools to evaluate the current state of infrastructure and systems and to develop appropriate intervention strategies. The articles of this themed issue present novel ideas and tools to support action at the municipal engineering level.The study by Bencekri et al. (2026) introduced the Walkability Planning Support System, a framework that uses high-accuracy multiscale regression to create diverse, data-driven urban design scenarios. An interesting finding of this study was a negative correlation between cycling and walkability, highlighting the urgent need for policies that balance these modes to prevent pedestrian–cyclist conflict.The article by Yu et al. (2026) also concerns walkability, with the authors having applied a walkability index to the granular connection points between different public transit modes, rather than just general street navigation. Its case study on the area around Gangnam Station, Seoul, South Korea, involved Geographic Information System (GIS)-based analysis on pedestrian networks and building data that demonstrated how specific facility improvements enhanced transit accessibility.In Pais et al. (2026), a scalable GIS-based methodology was developed to assess urban infrastructure specifically through the lens of walking and cycling friendliness. Its primary uniqueness lies in its ability to pinpoint ‘common problems’ shared by both modes, allowing policymakers to address multiple accessibility issues through single, efficient interventions. By applying this methodology to Coimbra, Portugal, the study provides a data-driven bridge between high-level policy goals and concrete, cost-benefit-analysed infrastructure plans.The article by Harding (2026) proposes a service design method for the assessment of built environments. Taking Farringdon Station, London, UK, as a case study, the method was used to examine whether this service-industry concept can solve long-standing inclusivity gaps in transport infrastructure. The article also introduced an innovative auto-ethnographic video method that captures real-time passenger friction, providing a replicable blueprint for designing more equitable public spaces.Actor–network theory (ANT) was used by Bernsteiner and Ninan (2026) to decode the complex sociotechnical decision-making process that allowed for the high-profile removal of a twentieth-century highway and the restoration of a canal in Utrecht, The Netherlands. It applied Michel Callon’s ‘translation’ concept to map how various stakeholders and technical elements influenced municipal decision making. The study provided a robust, qualitative framework for navigating the political and social hurdles of major sustainable transport transitions.Closing this issue, the paper by Yıldırım et al. (2026) provides a comprehensive review of recent literature on travel demand management (TDM), shifting the focus from building more infrastructure to strategically optimising what already exists through multimodal mobility. The review emphasised collaborative governance and argued that technical TDM interventions must be aligned with social equity and public health to be truly effective. It offers a future-focused roadmap for creating low-carbon urban environments that balance operational efficiency with human-centric goals.The methodologies developed and case studies presented in this Themed Issue focus on walking, cycling, waterway transport, and public transport, all of which are becoming increasingly central to sustainable transport systems. Themed Issue aims to provide useful insights and tools for both academics and practitioners and to promote the municipal engineer’s way of thinking, which is essential to the realisation of sustainable transport systems.
Fujiyama et al. (Wed,) studied this question.