A system of the present invention is capable of detecting, imaging and measuring both neutrons and gamma rays. In some cases, the system has a plurality of parallel plates each containing a plurality of detectors. The plates comprise non-PSD organic scintillation detectors, scintillation detectors having pulse-shape discrimination (PSD) properties, and inorganic scintillation detectors. In some other cases, the system has a plurality of scintillation rods radially distributed about a central axis, and the scintillation rods comprise non-PSD organic scintillation detectors, scintillation detectors having pulse-shape discrimination (PSD) properties, and inorganic scintillation detectors. A first plate or rod and a second plate or rod are used in connection to detect, image and measure neutrons and / or gamma rays.