What tool should a project manager use to efficiently manage project resources?

A simple list of project resources lacks the hierarchical organization and categorization needed to efficiently plan, allocate, and manage resources across project activities.

The Resource Breakdown Structure is a hierarchical chart that organizes all project resources - human, material, equipment, and supplies - by category and type. This structured view allows the project manager to identify resource needs, allocate them systematically, and track utilization across work packages. It is a formal tool specifically designed to support resource management planning in the PMBOK framework.

Project scope documents describe work to be done but do not provide the structured, categorized breakdown of resources required for efficient resource management.

Resource requirements identify what resources are needed for specific activities but do not provide the organizational structure for managing all resources across the full project.