I strongly believe the project management can be defined by two things; Scope Management and Stakeholder Management.
Scope Management ; involves the clear definition of the works, the budget and the project outturn and success criteria. And the monitoring of management of this scope to ensure that the agreed outturn is delivered, no more no less.
Stakeholder Management; ensuring that all stakeholders are fully informed and bought into the progress and direction of the progress. This includes people from Customers, Sponsors, Boards, End Users, Delivery Teams, Governance and Regulators to name just a view.
This is, in my opinion, the Holy Grail of project management.