A Project Manager is in the execution phase of a highly visible project and a major milestone is due in one week. The Project Manager has discovered that a vendor's deliverable for this milestone…

Concealing a known issue that will cause a missed milestone is unethical and violates PMI's standards for transparent stakeholder communication.

When a vendor deliverable will arrive two weeks after a one-week deadline, the PM must urgently engage the team to brainstorm workarounds - such as partial acceptance, parallel processing, or substitution - to minimize the milestone impact. This proactive approach demonstrates PMI's expectation that PMs actively manage and mitigate risks rather than simply documenting them. Acting immediately gives the team the maximum available time to implement a viable solution.

Halting vendor payments is a punitive contractual action that does not address the immediate schedule crisis and requires formal process to execute.

Reporting the missed milestone without a recovery plan is passive management that fails the team and stakeholders who expect proactive problem resolution.