The principle of public participation in policy-making and policy implementation features in many European Union directives and policy documents. It is also undeniably connected to the rise of what can be called the European e-society, in which digital technologies are expected to strengthen public involvement in democratic processes. One broad group of such technologies are commonly referred to as geo-visualisations.This book contains the results of a European project that explored the potential for using innovative geo-visualisation techniques in public participation processes for spatial planning. The approach taken in the project involved continual interaction between concept development, the technological possibilities, and their practical application in case studies conducted in Belgium, Poland, Portugal, Spain and the Netherlands. The structure of the book mirrors this procedure. Three chapters discuss the general concepts of spatial planning and participation, e-interaction, and innovation in organisations. Two chapters present the results of research into the communicative potential and the usability of 3-dimensional geo-visualisations.