Research was carried out in order to develop and test a prototype seismic tomographic system suitable for use in the exploration, mining and civil engineering industries. Prototype development involved redesigning existing seismic systems, development and assembly of compact units, and the production of new acquisition software and control software. There was particular emphasis on high dynamic range mechanisms and control mechanisms. The prototype system was named SUMMIT-Compact. The final version of the prototype SUMMIT-Compact is far more advanced than the earlier SEAMEX system. Each receiving unit handles 24 seismic input channels compared with 12 for SEAMEX, and up to 480 channels can be linked to a central control unit. The receiving units can be connected to the transmission cable at any position and, by using repeaters at 250 m intervals, the maximum cable length is unlimited. The data transfer time is 35 ms for one trace with 1024 samples. The prototype system was successfully tested in tomographic surveys at the Reocin underground and open-pit mine in Spain, the Grimsel rock laboratory for radioactive waste disposal in Switzerland and two Ruhrkhole AG sites in Germany. These surveys gave excellent results using drill holes from the surface or underground and in wet or dry conditions. The Exploration Area test work, carried out in deep drill holes, gave poor results because the open joints and cavities in the karstified dolomites reduced the strength of the seismic transmissions. The seismic equipment operated well and there is a strong possibility that the results would have been good in geological environments where the rocks are less affected by deep weathering. The seismic tomographic technique can be used immediately for short hole surveys of the type required by many civil engineering projects, such as dam construction, underground radioactive waste disposal projects and to assist specific mining problems. Furthermore, the technique has considerable potential for use in deep hole exploration in suitable geological environments.