Business students need to develop skills in the intelligent use of information, especially spatial information, for decision-making. Geographic Information System (GIS) is a viable tool for that purpose. Yet the few GIS courses in the Information Systems curriculum offered in various business schools tend to focus on different concepts and skills. In this paper, we examine the application of GIS in retail marketing. With access to appropriate data, GIS is an excellent tool for the analysis and identification of market opportunities. We describe a skill set of three specific approaches in GIS application using demographics data pertaining to potential customers and collected competitors' information. These approaches include visualization using choropleth maps, spatial overlay to classify feature information based on spatial correlation, and proximity analysis for site selection. These techniques allow us to identify where the potential customers are located, study competitor locations, and analyze opportunities for site selection. By identifying these techniques in the GIS skill set, we also discuss the pre-requisite knowledge for the students and what we may or may not emphasize in the design of GIS courses in the IS curriculum.