What is a Communication Management Plan?
The communication management plan defines who needs what information, when, in what format, and from whom — plus escalation paths and the technology used. It turns "we should communicate better" into an actual operating system for project information.
The classic exam fact behind it: communication channels grow as n(n−1)/2 — add people and complexity explodes quadratically, which is exactly why the plan exists.
Formula
Communication channels = n(n − 1) / 2
Worked example
A 40-person hospital-construction program's plan: owner gets a milestone dashboard monthly; the steering committee a one-page RAG report weekly; subcontractors a coordination meeting every morning at 7; safety incidents escalate to the sponsor within 2 hours, by phone, never by email. Nobody wonders who should have told them.