The Department of Homeland Security (DHS) is seeking proposals for enhancing mobile radiological/nuclear (R/N) detection through contextual information. Currently, mobile R/N detection systems are available but lack the ability to positively locate threats. Law enforcement personnel have to manually search for the source of radiation with limited information. DHS is looking for innovative approaches to integrate contextual sensors with modular, commercially available mobile radiation detection systems. The resulting system should be easily installed in an unmodified sport utility vehicle (SUV) within one hour and weigh no more than 200 pounds. The system should include a vehicle-mounted radiation detection system, contextual sensors, connections among components, and an output display for situational awareness. Additional capabilities of interest include distance calculation to the radioactive source, 3D rendering or point cloud with radiation overlay, 3D maps covering multiple city blocks, source activity level calculation, mapping of distributed radioactive sources, and recognition of environmental changes. Interoperability with Commercial-Off-the-Shelf (COTS) or modified-COTS vehicle-mounted radiation detection systems is preferred. The project duration and funding specifics are not provided in the document. For more information, refer to the solicitation notice and SBIR topic link.