The biennial conferences of the Society for Underwater Technology have achieved an excellent reputation for the quality of their presentations, which cover topics of the most acute current interest, as well as those at the forefront of review and development. The 1994 conference on subsea control and data acquisition formed no exception, since it covers subjects at the cutting edge of modern technology. It is a matter of increasing concern that products are becoming overspecified, resulting in excessive costs and longer development schedules, while not conferring an equivalent benefit in reliability of the finished product. This text is suitable for all subsea control system designers, manufacturers and operators, equipment consultants, application engineers, academics in the subsea engineering field, and all subsea engineers.