Project Networks

Back in the days when projects were dealt with by a single individual or a group of workers working sequentially, there was no need for project networks. As an example, consider the construction of a house. Somewhat simplistically, assume that a single individual wants to build a log cabin. He will first dig a hole in the ground for the foundation, then pour the cement, then lay the logs one by one, and so forth. Each job is completely finished before the next task begins. This is a sequential plan, and there is very little that can be done as far as planning is concerned. Consider, however, some of the issues that have arisen as a result of the division of labor. Nowadays, the plumbers can work at the same time the electrician does, but not before the walls have been established, which is also required for the roof to be put up. Given these interdependencies, planning is necessary in case time is an issue. Clearly, while it is

possible

that, say, electrician and plumber can work in the building at the same time, it is

not necessary

to use this parallelism: we can still have the two contractors work one after the other, if we so wish. The project will take longer, but it is possible. Project networks were designed by a number of firms in the