A tool, based on a geographical information system (GIS) approach, has been developed for the location and organization of public health care centers in Jeddah city, Saudi Arabia. The potential of GIS for visualizing and modeling available information on health-care has been utilized to produce a "best-fit application". This paper identifies and deals with the manner in which GIS can successfully be used for evaluating the demand and supply of health care facilities as well as be applied for defining health catchment areas. The study uses the essential achievements gained to analyze the advantages of GIS for health care planning and the location of health care centers. Some specific GIS tools, as well as single and multiple spatial search functions, are presented.