The overall objective of the proposal is to design, develop and demonstrate a potentially portable Compton x-ray scatter 3D-imaging system by using specially designed rotationally movable x-ray source and x-ray detector, and the development of a suitable 3D-processing computer model. The proposed rotational configuration will allow the acquisition of multiple projections or images 360° around the region of interest, probing a conical volume of the object to be interrogated. The subsequent application of a computer model on these multiple projections, developed during Phase I, will allow a three-dimensional reconstruction of the object under study. In the proposed x-ray imaging system, the primary technical advance will be to extend methods that normally supplied a 2D projected image through a sheet of material, to a 3D image with more complicated features at different depths, such as cracks, corrosion, voids, delaminations, land mines, or improvised explosive devices. Also, the proposed system will be potentially portable, allowing it to be brought to the object to be imaged. The Beta and Production Phases of the proposed system would incorporate a battery self-contained package and wireless data transfer capabilities. These systems would revolutionize the current imaging applications that rely on 2D x-ray imaging systems only.