This theme focuses on the use of online PPGIS methods as a method to enhance public participation. Many countries have legislated to realize participatory planning in all urban and regional planning projects. Despite the legitimacy offered by participatory approaches, challenges remain how to implement participatory planning in practice. Participation is rarely comprehensive enough, while the data produced seldom translates into influential knowledge. Research in this field concentrates e.g. on how the views of participants can (1) smooth the planning and design processes and reduce the number of conflicts, (2) promote adaptation to continuously changing societal conditions, (3) strengthen recognition of the differing values of various actors. (4) support learning and knowledge-building and (5) help to achieve tangible regeneration outcomes It is also important to study what kind of new skills and professional roles planners need to develop more usable and effective participation practices,