This chapter discusses how the need for geospatially enabled data messaging among emergency response agencies can be enabled with the Emergency Provider Access Directory (EPAD). It describes the directory, how it enables message routing and its fit into a boarder E-Safety network. It also discusses the architectural components of the EPAD, specifically the geographic information system (GIS) module, and how Web services and open source products were used in the design to enhance the EPAD service offering, an offering that has the potential to bring emergency agencies one step closer to realizing interagency interoperability for advanced response to emergency events.