The Statement of Work (SOW) is the one document that is often overlooked or underutilized but is critical to the successful delivery of a project, is the Statement of Work (SOW). The SOW is the supporting contractual document, which documents "what" is to be provided to a client and what is required to deliver a service or product successfully. Without a detailed SOW, you will be managing a project with an unknown objective. This, in turn, makes it difficult to determine what is to be accomplished, when you're finished, and what method will be used for measuring the success of both the PM and the project. Without a detailed SOW, you also have no baseline against which to measure progress or change.