ABSTRACT
Planning is simplified in a number of pragmatic ways, one of which is over levels (Figure 5.1):
• The project (work) is broken down (hierarchically) to lower level subprojects, sub-subprojects and so on to activities, elements and constituents. Subprojects may be chosen such that the interaction between subprojects is minimal and is commonly neglected, permitting subprojects to be planned independently of other subprojects. The same holds true where multiple projects are combined on an organisation level. However, interaction at levels lower than subproject is commonly strong. Interaction occurs because of the work method (implying an
order/sequencing of work). Iterations (between levels) can largely be removed by the planner being aware of what is happening on other levels when solving an individual level problem. The levels are uncoupled as far as possible, for tractability reasons, to make the level problems less complicated.
