In the last decades, a shift towards more democratic, participatory processes has occurred, rooted in the need to address environmental problems and climate change threats. Moreover, these participatory processes have been increasingly required in today’s spatial plans, strategies, and studies, for example, in Sustainable Urban Mobility Plans, Urban Climate Change Adaptation and Resilience Plans, and Sustainable Development Plans. In this context, academia and industry have built various public participation web-based solutions (ppWebGIS) and other geospatial participation tools to facilitate participatory procedures and support and inform the participants (planners, policymakers, citizens, etc.) towards spatial decision-making.However, despite the recent advancements in methodological and technological participatory geospatial tools, they are weak in addressing the complex issues found in “outlier” urban areas, i.e., areas with challenging conditions and characteristics. This paper introduces a comprehensive methodological framework for participatory spatial planning that conceptualizes and utilizes geospatial tools and platforms to address the challenges and opportunities in areas with special conditions. As part of an ongoing research program, the paper’s main contribution is to provide methodological innovation for participatory spatial planning in areas with special conditions through conceptualizing and implementing participatory geospatial tools to solve complex and multifactorial spatial problems.