Seismic radar was introduced as a geophysical tool for mineral exploration in the 1970’s. Since then, there have been several attempts to use the technique to assess civil engineering structures. For example: Bridge decks and masonry tunnels [1, 2], concrete [3], bridge decks overlaid with asphalt [4,5], concrete and masonry tunnels [6], detection of voids under jointed concrete paving [7], location of piles under an old concrete floor [8] and the location of leaks in underground pipes [9]. These few references are not intended to be a comprehensive survey, but do indicate the variety of problems for which radar has claimed to be the ideal inspection tool.