According to the PMBOK® Guide, specifically in the sections regarding Project Management Processes, a project is not a " one size fits all " endeavor. The act of choosing which processes are relevant to a specific project is known as Tailoring.
The Responsibility of Tailoring: The Project Manager and the Project Team are responsible for selecting the appropriate processes, inputs, tools, techniques, outputs, and life cycle phases to manage a project.
The Logic of Selection: Not every process, tool, or technique described in the PMBOK® Guide is required on every project. The PM and team must consider the project ' s size, complexity, risk, and organizational culture to determine what is " fit for purpose. "
Standard of Practice: While the Project Management Institute (PMI) provides the global standard, it explicitly states that the project management team is responsible for determining what is appropriate for the given project.
Collaboration: Although the Project Manager leads this effort, the Team provides the technical expertise and historical knowledge necessary to decide which processes (such as specific quality checks or risk analysis methods) are actually value-added for the project ' s unique constraints.
Comparison with other options:
A. Project stakeholders: While stakeholders have requirements and influences, they do not have the technical project management expertise to select the specific PMBOK® processes required to execute the work.
B. Project sponsor and project stakeholder: The sponsor provides resources and support, but they delegate the " how " of project management (the process selection) to the PM and the team.
D. Project manager and project sponsor: While the sponsor might sign off on the high-level approach (the Project Management Plan), the detailed selection of internal project processes is the functional responsibility of the PM and the team performing the work.