Stakeholders are anyone affected by or able to affect the project -- sponsors, team members, clients, regulators, or end users -- and a power/interest grid helps you decide how much attention each one needs: high-power, high-interest stakeholders require active management, while low-power, low-interest ones need only occasional updates. A communication plan specifies what information goes to whom, how often, and through which channel (email, WhatsApp group, status meeting, dashboard), preventing both information overload and dangerous silence. Messaging should be adapted to the audience: an executive sponsor usually wants a one-page summary of progress and risks, while a technical team member needs detailed task-level updates. Consistent, well-targeted communication is one of the strongest predictors of project success because it keeps surprises to a minimum.