Dear Edward:
Good day and thanks for asking these questions.
In the real word, different organizations might have slight differences in their interpretation of these documents. For example, at my current organization a project charter is called a ‘Project Initiation Document’.
PMBOK Guide is a set of best project management practices. Allow me to explain these documents from the reference of the PMBOK Guide:
1. The Statement of Work describes what the customer wants out of a project. For internal projects, the customer is your sponsor or the project initiator. This document can be a high-level document or a very detailed one. For external projects, this document is usually part of the awarded contract. For the external projects, the customer will usually compare the project deliverables with the Statement of Work.
2. The Project Charter is a document that officially recognizes a project, assigns a project manager and initiates a project. This is a very high-level document. It not only defines the project scope at a high level, but also addresses other areas such as high-level risks, costs, milestone schedule etc. The Develop Project Charter process takes the Statement of Work as one of the many inputs to the process to create the Project Charter. The Project Charter is usually an internal project document.
3. The Scope of Work is a project requirement. This gets documented in the Project Scope Statement which is a part of the project scope baseline. The project scope statement documents the project scope in much more detail in comparison to the project charter. Internally, the project team will compare their performance against the project’s scope statement. In comparison to statement of work, the project scope statement is more detailed and elaborated.
Please let me know if that answers your question.
Warm regards,
Khurram Hussain, PMP, CSSBB