Understanding innovation: the case of road pricing

Road pricing has emerged as an important transport-planning topic in several countries. This can be attributed to a growing concern for urban congestion and environmental problems, as well as to difficulties in financing new transport infrastructure. However, this innovative policy measure has rarely been implemented and consequently the Norwegian schemes have attracted much attention as exceptional examples of urban-wide road pricing. In this paper, factors contributing to the implementation of road pricing innovations are studied based on four Norwegian case studies. Different approaches to innovation research are discussed and a 'constructivist' approach is developed. This implies a focus on the meaning ascribed to road pricing measures by different actors at different times, on the alliances between important proponents and on innovation as an evolutionary process. The role of planners as facilitators of road pricing innovations is investigated. Factors describing 'simple' and 'complicated' contexts for road pricing implementation are outlined.