The document discusses the work breakdown structure (WBS), which is a key project management tool used to plan and organize a project. A WBS breaks a project down into smaller, more manageable components called deliverables. It has a hierarchical structure with the project goals at the top level and specific tasks and subtasks below. Developing a high-quality WBS involves iterative decomposition of deliverables, definition of work packages, and creation of a WBS dictionary for planning, tracking progress, and managing costs and schedules.