The world of computing got smaller in 1993 in terms of both new ultra-small computing systems and the downsizing of giant computer corporations. Yet for all its shrinkage, the computing industry also reached out in a big way. The new, small computers were equipped with wireless networking systems, and home and office computers were offered the promise of networking with other computers worldwide on a data superhighway. Today, computing is affecting work and leisure alike, increasingly involved in factory and business operations, networking, defence, medicine, education and the domestic environment. Computers and their systems are influencing attitudes to privacy, employment and other social issues. To this effect, the reader must remember that the construction of a system is as complex as a house built in a swamp. It does, therefore, require careful planning and design. Just as a house must have an architect's plan, so does a system. It must have requirements, system objectives and a blueprint.