A project charter is a 1-2 page document that authorizes the project and establishes its purpose, scope, and accountability. It is created before detailed planning begins. A project plan is a detailed document covering schedule, resource allocation, dependencies, and risk mitigation. The charter asks "why are we doing this and what will we deliver?" The plan asks "how exactly will we do it?" The charter comes first and sets the constraints within which the plan is built.

The project sponsor (the executive or senior stakeholder who owns the project and its business outcome) and the project manager should both sign the charter. In larger organizations, key stakeholders from departments directly affected by the project may also be signatories. The sponsor's signature is the most critical · it confirms they have authorized the project and are committed to providing the resources described.

One to two pages is ideal. A project charter that runs to 10 pages has become a project plan in disguise. The charter's purpose is to get alignment and authorization quickly · not to document every detail. If you cannot describe the project's purpose, scope, and success criteria on two pages, the project is probably not well enough defined to start yet.

Formally, a signed project charter should not change unless there is a fundamental change in the project's purpose or funding. Scope changes are managed through change orders or a formal change control process, not by amending the charter. In practice, if the business context changes dramatically, a revised charter can be issued and re-signed. Treating the charter as immutable gives it authority; constantly revising it removes that authority.

A business case explains why an investment is worth making, and a project charter authorizes the project that delivers it. The business case comes first. It sets out the need, the options considered, and the expected costs and benefits, so decision makers can choose whether to fund the work. The charter then draws on it: its purpose, objectives and high-level success criteria trace back to the business case. Keep the business case as its own document and reference it from the charter, so the sponsor can check the project against its original justification as the work runs. Source: Project Management Institute, A Guide to the Project Management Body of Knowledge (PMBOK Guide), Sixth Edition (2017).