The purpose of this research is to determine how the present use of Geographic Information Systems (GISs) can be improved for ill-structured problems in planning and design, While information-oriented GIS technology has proven useful for routine and administrative problems, it is not yet capable of providing information and knowledge interactively within a problem solving process that can be characterized as "ill-structured." This suggests that GIS technology must be embedded wi thin a large problem solving process for ill-structured problems. The hypothesis of this research is that implementation of conceptualization-oriented Spatial Decision Support Systems(SDSSs) will significantly improve the use of GIS technology for ill-structured problems.