A number of forces are bringing about fundamental changes in the way in which computing technology is applied in contemporary organizations. These include the transformation of society from one primarily dependent on the production of goods to one also much concerned with information and knowledge. Information technology has become a major support to humans and organizations in the development of new products and new services. One major change in organizations is that they have become more horizontal in structure. Reengineering, especially business process reengineering, is often used to accomplish this transformation. Other approaches, such as those based on total quality management (TQM), lead to organizational changes for improved quality and responsiveness. The technological enabler of each of these transformations is advanced information technology. It has enabled the construction of the information-system architecture of an organization to match the reengineered organizational structure and the desire for rapid communications throughout real and virtual organizations. In many cases, these are horizontal structures that require massively parallel communications capabilities between personnel in the organization. Client-server architectures and client-server systems are names generally given to these enablers of these transformations to new structural forms.