Good Practice: A large project should be cut up into more manageable sub-projects, which only depend on completed sub-projects. The project planning methodology provides an excellent tool to subdivide major projects into more manageable sub-projects with short-term deliverables.
Each project plan should be subdivided into several key milestones. This approach helps to provide continuous delivery and makes sure progress is measured regularly. For example, a recent large project involved two separate project plans for different stages of the project, development and implementation. Each plan consisted of around 300+ individual tasks and approximately 30 key milestones.
In his article 7 Steps to Project Success, Peter Draper suggests it is necessary to break up projects into smaller, independent sub-projects that are more easily manageable. These sub-projects must be:
Small, that is, less than $1m.
Fast, that is, takes less than 6 months.
Compact, that is, fewer than 6 people on the team.
Focused on key benefits and not just deliverables.
Going for a big bang implementation.
Not being prepared to take the extra cost of splitting the project into separate stages.
Underestimating the overall complexity and the interactions between all the different components.