You are a project manager of a large construction project. Within the project you are working with several vendors to complete different phases of the construction. Your client has asked that you…

Cost management tracks and controls the project budget and expenditures but is not the subsystem that authorizes or processes changes to contracted vendor materials.

Schedule management governs project timelines and work sequencing but does not control changes to the materials or scope defined in vendor contracts.

Materials that a vendor is contracted to procure and install are defined within the vendor's contract, so any change to those materials constitutes a contractual modification. The contract change management subsystem - part of the procurement management process in frameworks such as the PMBOK Guide - governs amendments to vendor scope, deliverables, and obligations. This subsystem must authorize and process the change before any procurement action can be taken.

Resource management addresses the allocation of labor and equipment to project activities but does not govern modifications to vendor-supplied materials or contractual deliverables.