Human factors in traffic

This chapter examines the psychological mechanisms underlying human behaviour in traffic and the challenges of promoting safe and sustainable mobility. It emphasises that information alone is insufficient to change behaviour; rather, road use is shaped by a dynamic interplay of internal factors (e.g. attitudes, values, cognitive dissonance, and perceived control) and external conditions (e.g. infrastructure, social norms, and vehicle characteristics). Several key theories are introduced, including cognitive dissonance, reactance, attribution theory, the theory of planned behaviour, situational and social comparison models, and the model of ecological behaviour. Together, these frameworks explain why individuals often struggle to “do the right thing”, despite knowing its benefits, and how interventions can reduce resistance and align behaviour with pro-social and pro-environmental goals. The chapter further explores the transtheoretical model of behaviour change, which outlines stages from pre-contemplation to maintenance, offering guidance on tailoring interventions to citizens’ readiness for change. Finally, Risser’s Diamond Model is presented as a comprehensive framework for understanding traffic as a socio-technical system, stressing that long-term, sustainable changes in mobility require coordinated strategies targeting both individual motivations and structural conditions.