What is an essential document for recording necessary changes in a project?

The change request is an essential document for recording necessary changes in a project because it formally captures the need for a change, the reason for the change, and the impacts that the change may have on the project. This document is crucial for the change management process since it helps ensure that any alterations to the project scope, schedule, or resources are properly evaluated, authorized, and communicated to all stakeholders. By using a change request, project managers can maintain project control and documentation, allowing for transparency and accountability throughout the project's lifecycle.

The project charter, while important, primarily outlines the initial project scope, objectives, and stakeholders rather than detailing specific changes. The project schedule focuses on the timelines and tasks of the project, not on documenting changes. The risk register is dedicated to identifying and assessing potential risks associated with the project, rather than tracking changes in project scope or execution. Thus, the change request stands out as the critical document for managing and recording changes effectively.