A radiation detection, localization, and identification system uses a searching algorithm to identify hypothetical solutions to Compton scatter data. Model based representations of the physical data collection yield the identity and location of radiation sources when correct associations of gamma ray energies and locations are made with detected data events. The system's detector is an array of radiation detectors networked to act as a single detection system. This network has wide area of view and high sensitivity to radiation sources since no collimation is required.