Abstract: Software for interactive choropleth mapping typically focuses on design, with the assumption that the resulting map will be used like a traditional paper one. We believe that interactive graphics also should enable users to explore the database underlying a map. In this vein, we have developed software that will permit users to both design a map and explore the underlying database. The exploration component, the raison d'etre for the software, includes the following options: Overview, Areas, Reclass, Regions, Tables, and Graphs & Stats. Within Overview, users can display map elements in sequence, any combination of classes, and highlighted subsets of the data. Within Areas, users can determine values associated with areas, compare values for two areas, and determine minimum and maximum values for classes and the entire map. Reclass allows users to reclassify the map data temporarily, thus determining the effect of different classification schemes. The Regions option permits regions to comprise sp...