Transparency, flexibility, simplicity: From buzzwords to strategies for real PSS improvement

There is a growing body of academic literature that deals with the gap between Planning Support Systems (PSS) and daily urban planning practices. In response to the identified bottlenecks for implementation and insights from knowledge management, a new approach for improving PSS implementation was recently proposed. This Mediated Planning Support (MPS) approach is grounded in several theoretical schools, such as knowledge management and cognitive science. This article discusses the testing of this approach in three cases of land use and transport strategy-making in the Netherlands, with the aim to increase the understanding of the added value of the mechanisms that underlie the MPS framework. Methodologically speaking, it utilised workshop specific surveys, a general ex-post survey and participatory observation. Although small-N, the results seem to indicate that MPS does improve several of the bottlenecks of PSS implementation defined in other studies: it provided a better fit between the PSS characteristics and the strategy-making processes, it increased understanding of the possibilities (and limitations) of PSS, it fostered acceptance and improved use (awareness and transparency were not significantly influenced). Important mechanisms for promoting these outcomes include an open constructive critical attitude of both PSS developers and planners, a prototyping process, and placing emphasis on externalisation and internalisation of knowledge. The paper closes with a discussion on the implications for PSS development and planning and will provide directions for further research.