ABSTRACT
This chapter introduces critical path network analysis. Proficiency in both the use and understanding of networks requires some initial learning and practice and, perhaps, a degree of aptitude in the application of logical argument. Network analysis, and particularly the use of arrow diagrams, gave planners a valuable new tool with which they could express the logic of a proposed work plan for their projects. Some people might wish to use networks only on their computers, always drawing them directly on the screen. The heart of any activity-on arrow system is the arrow diagram, logic diagram, or 'network', itself. Dummy activities are usually unnecessary in precedence networks, but they can be useful as start and finish activities or as interface activities common to two or more different project networks. Construction of the network diagram is carried out in the same way for both methods, the main difference only becoming apparent when the time comes to estimate activity durations.
