The transition from analogue coaxial cable to digital optical fibre submarine systems has required a new technology to be established and complementary technologies to be developed for the design, evaluation and operational support of these new systems. The common design parameter throughout is reliability; not only must the overall system design satisfy the reliability objective but the component parts must be shown to exhibit the necessary low level of failure for this to be achieved.1988 sees the commissioning of TAT-8, the first trans atlantic optical fibre submarine cable system. In addition a number of submarine cable systems linking the UK mainland with other British Islands and Europe will be made available. This paper reviews the current generation of submarine cable systems based on 1.3μm and emerging 1.55μm technologies and discusses the opportunities offered to planners and network operators from developments in networking, optical repeaters and non-silica fibres.