There are two business documents that are crucial to project management endeavor, business case and benefits management plan. These two documents are kept separately from the program framework and don't combine with project management and its individual plan components.
Both of these two documents depend on each other, and they are continually refined and developed as the project goes on. The project sponsor is primarily accountable for developing and updating the project business case. Both documents are also a part of project management artifacts.
As a project manager, he is accountable for providing insight, evaluation, and oversight for the pmp business case, project management plan, project charter, and benefits management plan as these goals pertain to alignment with the project and organization's objectives. The noted project management documents should be customized appropriately and specifically for each project undertaken by the project manager.
Business cases are documents that explain whether a project should be undertaken, or not. If the answer is yes, it also explains why to do and what to do from a high-level perspective. Information about the scope, goals of the project, anticipated outcomes, expenses, and payoffs can be found there.
A project benefits management plan is about how and when a project’s benefits will be delivered. Regardless of when the project is started, it should result in a tangible benefit.
See also: Business Justification Analysis