Statement of Work (SOW) vs Project Scope Statement for PMP Exam

In the Project Initiation Process for the PMP Exam, there are several documents that are created as the basis for understanding the scope and other requirements of the project, e.g. Project Charter, Business Case, Project Statement of Work (SOW), Project Scope Statement, etc. The latter two, namely, “Statement of Work (SOW)” and “Project Scope Statement” are often confused by Aspirants. This post will help you understand their similarities and differences and help you select the right answer in your PMP Exam.

Additional FREE PMP resources: 47+ Commonly Confused Term Pairs with detailed explanations. If you found this article useful, you may wish to reference other Commonly Confused Term articles.

Statement of Work (SOW) vs Project Scope Statement

• Statement of Work (SOW) : is also known as Project Statement of Work (to distinguish with Procurement Statement of Work) is a document including the high level description of the intended deliverables of the project.
• Project Scope Statement: a document including more details than Project Statement of Work on the scope and deliverables of the project, major assumptions and constraints are also added if appropriate.

From the PMOBK Guide definitions, it seems that both Statement of Work and Project Scope Statement are very similar as they both contains the descriptions of the project deliverables. However, when researched in more depths, it can be found that:

• Statement of Work (SOW) contains high level information of the project deliverables
• Project Scope Statement contains more details of the deliverables plus assumptions and constraints

Illustrated Example

Statement of Work (SOW) contains at least the following three elements:

1. Organization strategic plan
2. Business needs
3. High level product scope

These are meant to provide an overarching direction for the project only, NOT the full implementation details. The high level product scope contained in the statement of work must be further developed in order for all stakeholders and project team members to really understand what are expected from the project. This is where the Project Scope Statement comes into play.

Project Scope Statement on the other hands includes lots of details for the project (not necessarily include all of the following):

• objectives
• project scope
• product scope
• requirements
• boundaries
• deliverables
• acceptance criteria
• constraints
• assumptions
• milestones
• cost estimation
• specifications
• configuration management requirements
• approval requirements
• etc.

The Project Scope Statement may be elaborated progressively over time when more details on requirements and constraints are known during the requirements collection and scope defining processes.

Note also that the Project Scope Statement together with Work Breakdown Structure (WBS) and WBS Dictionary form the Scope Baseline.

Which Comes First?

These two terms are often confused in real-world practice as project managers may use the two terms interchangeably to refer to documentation containing all the work to be done for the project. But according to the PMBOK® Guide (as the PMBOK® Guide is intended for medium to large scale projects), the Statement of Work (SOW)  would only contain very high level scope while the Project Scope Statement contains the full details.

Since the Statement of Work (SOW) contains a high level description of the project scope while the Project Scope Statement contains the lower level (more detailed) description of the project scope, it can be easily inferred that the Project Scope Statement is developed from the contents of the Statement of Work (SOW). So the following documents need to be developed in sequence:

1. Project Statement of Work (SOW) – documenting the very first ideas for the project
2. Project Charter – formally authorising the project and project manager (= SOW + Business Case + Contract)
3. Project Scope Statement – when the project manager is collecting requirements and defining scope

Project Statement of Work (SOW) vs Procurement Statement of Work (SOW)

As its name suggest, the Procurement Statement of Work is to be created during Project Procurement Management. It contains enough detail to allow potential sellers to decide whether they are qualified or beneficial to pursue the project work. The Procurement Statement of Work includes the following elements:

• performance (describe what can be accomplished)
• functional (convey the end purpose or result)
• design (convey precisely what are to be done)

The Procurement Statement of Work may be developed by either the seller or buyer. You will just need to remember that the Project Statement of Work (SOW) is mostly intended for internal use while the Procurement Statement of Work (SOW) is for always for external use.

Additional FREE PMP resources: 47+ Commonly Confused Term Pairs with detailed explanations. If you found this article useful, you may wish to reference other Commonly Confused Term articles.