Over three decades, the Spatial Decision Support System (SDSS) concept has evolved significantly exploiting information technology to assist decision maker in a variety of fields of research, development, and practice. With the communicative turn in planning, which emphasizes public participation in all levels of planning and decision making, these technologies have further matured to support participatory planning by means of supporting diverse stakeholders in the decision making process. However, for multiple reasons, SDSS are still in the domain of expert, largely failing to incorporate general citizens in its use and applications. On the same note, citizen science as a method of inquiry is gaining much attention in recent years to engage general citizens in the scientific research, thereby also empowering them to participate in the decisions of the issues affecting them. As such, it seems likely that citizen science shows great promise for advancing SDSS for achieving broad citizen engagement in planning and decision-making. This paper discusses the strengths, weaknesses, opportunities, threats (SWOT) of integrating citizen science with SDSS by analyzing existing literature on SDSS and citizen science. In particular, we explore the integration of aspects of citizen science in Interactive Planning Support System (PSS), as one form of SDSS to support wider citizen engagement.