Abstract: A highly directional radiation probe with a laser guide to pinpoint the position of a source of radiation. The probe is configured with a lead pinhole collimator, a radiation detector configured to detect radiation through the pinhole, and a laser positioned in the collimator and configured to project a beam through the pinhole. When the probe is aligned with the radiation source detected through the pinhole, the laser is activated and projects a beam at the source position. The probe can scan a person in three dimensions to quickly locate radioactive shrapnel for removal. The probe can also be used to pinpoint small sources of radiation in a localized area within a radius up to about 20 meters or further, depending on the level of radiation exposure encountered. The probe is adapted to be hand-held, battery-operated and used with a visual or audible radioactivity indicator or a visual display device.