The Scope Baseline: Project Scope Statement, WBS, and WBS Dictionary

PMBOK v8 Definition

The scope baseline is a component of the project management plan and consists of the approved version of a scope statement, work breakdown structure (WBS), and its associated WBS dictionary. The project scope statement includes the description of the project scope, major deliverables, and exclusions. The WBS is a hierarchical decomposition of the total scope of work to be carried out by the project team to accomplish the project objectives and create the required deliverables. Each descending level of the WBS represents an increasingly detailed definition of the project work, with the lowest level being a work package with a unique identifier.

Why It Matters for the Exam

The scope baseline appears frequently on the PMI exam because it is the fundamental reference document against which all project scope performance is measured. Questions test your ability to distinguish between its three components, understand when it is created (during planning), and recognize that changes to the scope baseline require formal change control procedures. Expect scenario-based questions asking which document to consult for specific scope information or what constitutes a scope baseline change.

Key Points to Remember (for the exam)

• Three Components: Scope baseline = Project Scope Statement + WBS + WBS Dictionary
• Main Output: Scope baseline is an output of the Develop Scope Structure process (predictive approach)
• WBS Definition: A WBS is a hierarchical decomposition of the total scope of work to be carried out by the project team
• Work Package: The lowest level of the WBS is a work package with a unique identifier
• Project Management Plan: The scope baseline is a component of the project management plan
• Predictive Approach Only: In projects using a predictive approach, the WBS together with the project scope statement and WBS dictionary constitutes the scope baseline
• Common Confusion: The scope baseline is NOT the same as the scope management plan; the scope management plan describes HOW scope will be managed, while the scope baseline defines WHAT the scope IS

Typical PMI Exam Example

A project manager is reviewing the approved project scope with stakeholders. A stakeholder asks to see the detailed breakdown of all work packages and their descriptions. Which document should the project manager reference?

Correct answer: The WBS dictionary, as it contains detailed information about each work package in the WBS.

PMI Exam Traps

• Trap: Confusing the scope baseline with the project scope statement alone

  • Reality: The scope baseline includes ALL THREE components: scope statement, WBS, and WBS dictionary

• Trap: Thinking the WBS is a list of activities or a schedule

  • Reality: The WBS is a hierarchical decomposition of deliverables, NOT activities or tasks

• Trap: Assuming the scope baseline is created during the Define Scope process

  • Reality: The scope baseline is created during the Develop Scope Structure process (predictive approach)

• Trap: Believing the scope baseline can be changed without formal change control

  • Reality: Any changes to the approved scope baseline require formal change control procedures

Important PMI Connections

Quick Review Questions

1. What are the three components that make up the scope baseline?

2. In a predictive project approach, during which process is the scope baseline created?

3. What is the lowest level of the WBS called, and what unique characteristic does it have?

4. If a stakeholder needs to know the detailed description of a specific work package, which scope baseline component should they consult?

5. What type of procedure is required when changes to the approved scope baseline are needed?

PMBOK v8 Reference

Section 2.2.2.4 - Develop Scope Structure (Predictive Approach) Section 2.2 - Scope Baseline Definition and Components