Geographic information systems emerged in the 1970s and have become significant decision-making tools as their capabilities have been enhanced. This chapter includes a brief discussion of various GIS applications and a more detailed discussion of issues that public managers should consider when evaluating implementation of a geographic information system. GIS applications provide benefits at the basic level in terms of producing maps efficiently, at the planning level through the use of database applications, and at the management decision-making level through an ability to access relational databases for policy-level decisions. In considering the capacity of GIS in the public sector, concise definitions of the major application theories—vector and raster—are offered to provide a basic understanding of the analytical process and GIS toolkit aspects. Issues impacting GIS implementation include needs assessment, project planning, access to public records, liability issues, public and private partnerships, dissemination of information, and privacy issues. Public managers should be aware of difficulties associated with justification of costs associated with GIS implementation and that a hesitancy exists on the part of GIS program managers to share missteps and implementation failures.