As has often been stated, a business of any size can be considered as a general system,8,11,13,28,29,20,31with identifiable external inputs and outputs typically consisting of goods, services, energy, money, and information. Internally, a business consists of several interacting parts which may be considered as subsystems, each of which has inputs from external sources or from other subsystems and outputs to external sinks or to other subsystems. Usually, each subsystem requires information as an input and, in turn, generates information as an output. As a business becomes larger and more complex, the need for information becomes greater and more critical.