The object of the thesis of Maarit Kahila-Tani was to study the potential of PPGIS tools to support participatory urban planning. The research analysed a set of SoftGIS and other PPGIS studies conducted during the period 2004-2015 in varying research and urban planning projects in Finland. The thesis adopted a normative approach to the question of how various PPGIS tools could be embedded more securely into the urban planning process. The thesis constructed a heuristic conceptual model for a participatory planning support system (PPSS), based on the experiences of applying PPGIS tools.

The central observations of this thesis reflect the numerous ways in which PPGIS tools and experiential knowledge can support planning during the different stages of the planning process and in relation to different planning tasks. At best, PPGIS methods can produce multifaceted information, especially in the early phases of the planning process. Data gathering however remains effectively characterised as singular interventions to harness specific information for the direct purposes of the ongoing planning task. Embedding this experiential knowledge more fully into the planning system currently rests almost exclusively on the shoulders of individual planners. Grafting PPSS onto the planning system requires a rather more strategic approach to participation.