Although GIS has been in existence for over 20 years, the systems have only recently matured to the point where they have become accessible to geographers, planners, environmental scientists and others as an affordable and practical tool for spatial analysis. Much of the GIS literature is scattered over the journals and technical reports of a number of disciplines. These sources are often not widely available especially to the newcomer to the field. This text was assembled to bring together what we believe is a balanced sampling of written works that cover important aspects of the basic principles involved in GIS, as well as to provide some examples of GIS applications.