Geographical Information Systems (GIS) are now a widespread and important form of Information Technology (IT) use. In principle, Information Systems (IS) research is concerned with all forms of IT use. Yet despite this importance, GIS remains largely invisible in IS research. This paper illustrates this separation using bibliographic data drawn from both GIS and IS. It reviews discussion within IS as to the nature of the discipline and argues for a closer coupling between IS and GIS. It discusses Spatial Data Infrastructure (SDI), mobile computing and public participation GIS as examples of spatially related fields where further IS research would be beneficial.