Toward a conceptual framework of hard and soft behavior change interventions in sustainable transport

This paper aims to identify effective strategies for promoting behavioral change toward more sustainable travel patterns, drawing on evidence from the literature and practice. Established objectives for behavior change interventions include reducing emissions, alleviating congestion, and enhancing overall well-being through targeted interventions. Drawing on existing frameworks for behavior change, the paper focuses on the key dimensions which are relevant to the design and evaluation of policy measures. A multi-dimensional conceptual framework of behavior change interventions in transport is proposed to highlight the importance of combining ‘hard’ measures, such as road user charges and infrastructure investments, with ‘soft’ measures, like public awareness campaigns and incentive programmes and working from home. The other three dimensions cover the timeframe for change, the level of change impact and the “push” and “pull” change strategies. Evidence of previous impact is presented, distinguishing between marginal and non-marginal changes and, where appropriate, the longevity of impact. The evidence demonstrates that tailoring these strategies to specific population segments and geographic contexts is crucial for delivering impact, particularly given the diverse travel needs and socio-demographic factors that exist within different jurisdictions. The paper concludes with recommendations for advancing research to better understand the synergetic effects of various behavior change interventions using the proposed framework whilst also recognizing that measures to minimize travel must be seen in context.