Challenges in Addressing Messiness and Uncertainties in Sustainable Transport Planning with Participatory Interventions


  • Peraphan Jittrapirom Radbound University
  • Vincent Marchau Radboud University
  • Rob van der Heijden Radboud University
  • Ruben Aske Radboud University
  • Yuko Onishi


Mobility Policies, Intervention, uncertainty, participation




The transition towards a more sustainable transport system is a complex and multifaceted process surrounded by uncertainties. This complexity stems from the involvement of diverse stakeholders within the transport sector, each with their own perspectives, visions or desirable future, and preferences regarding what constitutes sustainability, the current challenges, and the most suitable solutions, measures, and policies to achieve sustainable outcomes. The related uncertainty, on the other hand, arises from the future aspect and the long-time horizon that is concerned with the transition, both internal and external to the transport system, such as an unknown about travelers’ adoption of a new mobility service (internal), a wide implementation of self-driving vehicles (internal), and a resurgent of Covid-19 pandemic (external).

This amalgamation of complexity and uncertainty poses significant challenges that can impede or slow down the successful realization of a sustainable transport system. To navigate these challenges, various research methods have been proposed and applied, including the visioning process, participative group model building, and dynamic adaptive planning. These methodologies aim to assist decision-makers and stakeholders in understanding and addressing the intricacies of sustainable transport planning and implementation.

In this paper, we critically examine the challenges encountered in applying these methodologies to support decision-making and practice in sustainable transport. We highlight both the vulnerabilities and opportunities inherent in these approaches, with a focus on issues such as stakeholder identification and engagement, elicitation of future visions, and managing uncertainty. To illustrate our discussion, we present three case studies wherein we employed Robust and Generative Visioning, Participative Group Model Building (GMB), and the Dynamic Adaptive Planning process.

To structure our reflections, we draw upon the framework of knowledge integration in transdisciplinary research and the analytical lens of Decision Making under Deep Uncertainty. By leveraging these frameworks, we elucidate the nuances of our findings and provide insights into potential avenues for future research. Overall, this paper contributes to the ongoing discourse surrounding sustainable transport by offering a critical examination of methodologies aimed at navigating complexity and uncertainty. By identifying key challenges and opportunities, we aim to inform and inspire future research endeavors aimed at fostering a more sustainable transport system.