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A coded aperture, germanium-detector based gamma-ray imaging system has been designed, fabricated, and tested. The detector, cryostat, and signal processing electronics are discussed in this paper. The latest version orthogonal strip planar detector is 11-millimeters thick, having 38x38 strips of 2-millimeter pitch. The planar detector was fabricated using amorphous germanium contacts. The strips on each face of the detector lie in a chorded-circular pattern to more efficiently utilize the area of the 10-cm diameter germanium crystal. The detector is held in a mount that allows convenient installation and removal of the detector, lending itself to eventual tiling of such detectors into large arrays. The cryostat includes provisions to install a large volume coaxial germanium detector immediately behind the planar detector in the same cryostat. Many gamma rays Compton scatter from the planar detector into the coaxial detector. The energies of these coincident interactions are summed to increase the gamma-ray detection efficiency for higher energy gamma rays (> 200 keV). This hybrid detector configuration recovers many of the gamma rays that would otherwise scatter out of the planar detector. Each strip is read out with a compact, low noise, external FET preamplifier specially designed for this instrument. A bank of shaping amplifiers, fast amplifiers, and constant-fraction discriminators provide readout information that includes 3-dimensional position information on multiple simultaneous photon interaction positions in the detector at the 2 mm level. The energy deposition at each location is also read out with germanium spectroscopy grade resolution. This information is sent to a computer where the image is formed. The excellent energy resolution of the germanium detector system provides isotopic imaging. [ABSTRACT FROM AUTHOR]