This study compares the risks in transporting spent nuclear fuel and high-level radioactive waste under three rail shipment alternatives: 1) regular train service, operating without restrictions with the exception of current hazardous materials regulations; 2) dedicated train service, operating with consist and operational restrictions; and 3) key train service, similar to regular train service with the additional speed limitation of 50 mph. Dedicated train shipments have a lower overall radioactivity exposure risk during incident-free transport than shipments by regular or key trains; the advantage is primarily derived from the differences in the duration and frequency of yard visits, which account for a significant portion of total exposure for impacted populations. Crew population doses, however, are higher for dedicated trains because of crews working closer to the cask. Estimated population group exposures are low and do not include any additional protective measures, which may be implemented to mitigate exposure.