What document defines the project's objectives and overall purpose?

The project charter is a vital document that outlines the project's objectives, overall purpose, and high-level requirements necessary for achieving those objectives. It serves as the foundation for the project, establishing the initial scope, stakeholders, and constraints. This document is typically created early in the project lifecycle and is essential for gaining approval from sponsors and stakeholders.

By clearly defining the project's goals and aligning stakeholders' expectations, the project charter facilitates communication and sets the direction for all subsequent planning and execution. It ensures that everyone involved has a shared understanding of the project's intended outcomes.

In contrast, other documents such as the project plan provide detailed schedules, resources, and execution strategies, while the statement of work focuses on the specific deliverables and work required. A risk management plan identifies potential risks and strategies to mitigate them but does not encapsulate the overall purpose and objectives of the project. Thus, the project charter is the central document that articulates the "why" behind the project, making it the key element required for project initiation.