Abstract: MRRI has been communicating spatially explicit data and information about the Hackensack Meadowlands District in northern New Jersey since 1992. A regional initiative to share GIS resources with and among local governments was approved under the Municipal Assistance Program. One component of the program was to develop the Emergency Reponse Information System (ERIS); a customized GIS tool that integrates critical information from Right-To-Know databases which are easily queried and displayed using mapping services that are available through the Internet and on standalone laptops provided to emergency town officials. The ERIS application is currently deployed on emergency vehicles and on Interactive Mapping Service (IMS) and a Google Earth-based application designed to be accessible from the web.