The model of communication presented in Figure 1 provides a useful heuristic to apply to the cases presented above. The model distills considerations in the Critical GIS literature related to multiple co-existing realities of landscape, unequal access to data and technology, and the necessity for plurality and participation, so as to identify points in the process of GIS-supported production of information and decision-making where stakeholders can be engaged in the production and representation of knowledge. If embedded within participatory and collaborative processes, this engagement can be empowering for communities and might avoid social and spatial marginalization for which traditional applications of GIS technology have sometimes been criticized.
An important point to draw out of this discussion, particularly from the PPGIS and PGIS applications to the Cooum River and Chennai slum community projects, is that necessary scientific and technological expertise needs to be complemented by expertise in collaborative methodology and participatory development. There is a popular saying that “when all you have is a hammer, everything looks like a nail.” The point is not to throw away the “hammer,” but to use it in conjunction with a more full conceptual and methodological toolbag. Methods and tools (such as GIS) should be chosen and applied in a manner responsive to characteristics and contexts of problems, not according to disciplinary or epistemological stances. In most cases this will entail the work of an interdisciplinary team and requires openness to defining problems and discovering an appropriate methodology in collaboration with stakeholders.