Projects can be categorized usefully as basic, major, or macro projects. The project type is determined by the number and variety of tasks required for the project's completion. A project that needs 30 or fewer task leaders and works within one technology or methodology fits the definition of a basic project. It has one project manager and one project management team that is made up of the project's task leaders.
A major project requires more than 30 tasks leaders and/or requires leaders who each have a different technical expertise as managers. A major project breaks down into several basic projects, each with their own basic project manager who leads the planning and execution of the basic project. Each basic project works to a specification that was developed by the basic project manager for the major project manager. The major project manager acts as the sponsor for each basic project and is the coordinator of the several basic projects within the major project.
The work breakdown structure for the macro project identifies several different effort areas, which are necessary for the project's execution and which must be coordinated to achieve the project's specified output. It differs from the work breakdown structure in a major project in that the areas of effort do not break down directly into basic projects but require several layers of breakdown before they are reducible to a family of basic projects.
To achieve success, macro projects require project management teams to define their specifications at each level and to coordinate the efforts of the leaders of subordinate projects.
Major and macro projects cannot reliably predict a project's feasibility, cost, and duration until the planning work on each of the component basic projects is completed.