Stimulated by debate surrounding the potential siting of a national repository, critical issues related to transporting high-level radioactive material (HLRM) are emerging. Techniques such as route characterization and risk/impact analysis are being developed or refined to facilitate routing decisions. Key inputs to analysis include demographic data, environmental features, and transportation system characteristics—inputs that are spatial in nature and difficult to manage without appropriate technology. This paper demonstrates the application of geographic information systems (GISs) to HLRM transportation analysis and identifies three transportation risk-analysis methodologies: comparative study, worst-case assessment, and probabilistic risk assessment. While known for its ability to integrate, manage, process, and effectively present large amounts of complex spatial data, the GIS technology potential for HLRM transportation risk analysis has not been fully exploited. This potential is demonstrated here in applications of GIS technology to develop estimates of resident and visitor population and ecologically sensitive areas along transportation corridors. The applicability of GIS technology is also illustrated through a discussion of linking models for risk assessment and examples of effective display of data and results.