Having identified the work packages through the work breakdown structure, the project manager has a good idea of the skills required of the project workers.
The skills necessary for building a house, for example, are clearly implied. A house must have a foundation. Because installing a foundation is a work package that involves placing forms and pouring cement, it requires the skills of masons. Walls also are a necessary element of a house; construction of these walls is obviously a work package for skilled carpenters. A house must be wired for electrical services; wiring is a work package for electricians. Small workgroups of masons, carpenters, and electricians, headed by the lead specialist in each group, will work on the house. Installing window shades is yet another work package, but it is one that does not require a workgroup. A single specialist can do this type of work. This specialist also will serve on the project team, along with the lead mason, electrician, and carpenter.
Unless the project manager is an experienced contractor, discussing the work packages with actual contractors to ascertain that no packages have been left out, clearly is in order. The same is true of the electricians, masons, carpenters, and other workers on the project. Talking with them could unearth a work package that so far has been overlooked.
Erecting a larger building is another matter entirely. One level of breakdown will not produce enough details to expose the skills needed to build a skyscraper. The site preparation for a building of this magnitude may require a survey and an excavation. This adds another level of breakdown, which clearly reveals the need for survey and excavation crews. By pursuing this process of breaking down work packages into smaller and smaller groups, the project manager will eventually nail down all the workers needed to build the skyscraper.
However, there is no need to go it alone. Seeking the advice of knowledgeable and experienced project managers and skilled workers, called "subject matter experts," can greatly help identify the work packages. Such people are always around an organization. They have learned what to do and how to do it, and they may share their notes and documents, such as Gantt charts or resource tables. Because the project manager is not expert in all areas of project work, he or she must rely on the advice of those who are.