Effective Project Management: Traditional, Agile, Extreme, Sixth Edition

Understanding the Scope Triangle

You may have heard of the term “Iron Triangle.” It refers to the relationship between Time, Cost, and Scope. These three variables form the sides of a triangle and are an interdependent set. If any one of them changes at least one other variable must also change to restore balance to the project. That is all well and good, but there is more to this triangle.

The following five constraints operate on every project:

• Scope
• Quality
• Cost
• Time
• Resources

These constraints form an interdependent set — a change in one constraint can require a change in one or more of the other constraints in order to restore the equilibrium of the project. In this context, the set of five parameters form a system that must remain in balance for the project to be in balance. Because they are so important to the success or failure of the project, each parameter is discussed individually in this section.

Scope

Scope is a statement that defines the boundaries of the project. It tells not only what will be done but also what will not be done. In the information systems industry, scope is often referred to as a functional specification. In the engineering profession, it is generally called a statement of work. Scope may also be referred to as a document of understanding, a scoping statement, a project initiation document, or a project request form. Whatever its name, this document is the foundation for all project work to follow. It is critical that the scope be correct. Chapter ...