The first part of the report provides detailed descriptions of the desktop geographic information system (GIS) applications of ArcView, MapInfo, and GeoMedia. These descriptions encompass assessments according to a number of concerns that police agencies express when attempting to select appropriate mapping technologies, i.e., general characteristics; data types, acquisition, and manipulation; map creation functionality; possibilities for customizing the software; and highlights of recent upgrades to the products. A summary form provides facts on required resources, supported data, and strengths and weaknesses of each product. The second part of the report consists of a general review of software products with utility for police agencies. This review encompasses over 120 computer software products, including information on their capabilities, platforms, and contact information. Many of the products reviewed were developed as extensions to one of the three main mapping software packages described in the first part of the report. Others are stand-alone products that function separately from and perform functions independent of the three main products described. The third part of the report provides general information on crime mapping software adaptations that have been developed by specific police agencies. A list of products, 3 references, and appended questionnaire used in the survey of agencies to determine their adaptations of GIS software applications.