An integrated neutron-gamma radiation detector includes a gamma sensing element, a neutron sensing element comprising a neutron scintillating material at least partially surrounded by an optical waveguide material, and a photosensing element optically coupled to both the gamma sensing element and the neutron sensing element. A portion of the gamma sensing element is capable of being disposed within a central aperture of the neutron sensing element. In one aspect, the neutron sensing element comprises a plurality of cylindrical, concentric shells forming the central aperture for receiving the gamma sensing element. In another aspect, the neutron sensing element comprises a plurality of strands forming a multi-layered structure and forming the central aperture for receiving the gamma sensing element.