Resource Breakdown Structure: Team vs Physical Resource Plans
PMBOK v8 Definition
The Resource Breakdown Structure (RBS) is a hierarchical representation of resources by category and type, used for planning, managing, and controlling project work. Each descending level represents an increasingly detailed description of the resource until the information is small enough to be used in conjunction with the WBS to allow the work to be planned, monitored, and controlled. According to PMBOK v8, the RBS may be divided between the team management plan and the physical resource management plan according to the specifics of the project.
Why It Matters for the Exam
The RBS appears frequently in PMI exam questions testing your understanding of resource planning and organizational structures. Questions typically ask you to distinguish between the RBS and other breakdown structures (WBS, OBS), identify where resource information is documented, or recognize how resources are categorized at different hierarchy levels. Expect situational questions where you must select the correct breakdown structure for a given resource management scenario.
Key Points to Remember (for the exam)
- Hierarchical Structure: RBS organizes resources in descending levels, from broad categories (e.g., personnel, material, equipment) down to specific types (e.g., Grade 2, Level 1)
- Dual Application: The RBS can be split between the team management plan (for human resources) and the physical resource management plan (for materials and equipment)
- Integration with WBS: RBS is designed to be used in conjunction with the WBS to plan, monitor, and control work at detailed levels
- Resource Categories: Standard RBS categories include Role, Personnel, Material, and Equipment, each with sub-levels (Level 1, Level 2, Grade 2)
- Resource Management Plan Component: The RBS is part of the resource management plan, which describes how project resources are acquired, allocated, monitored, and controlled
- Identification Method: The RBS helps identify and quantify both team and physical resources needed for the project
- Control Purpose: Each descending level provides increasingly detailed descriptions until the resource information is actionable for project management
Typical PMI Exam Example
A project manager is planning resources for a construction project. They need to organize all required resources hierarchically, starting with broad categories like personnel and equipment, then breaking down into specific types such as "Electricians" and "Crane Operators." Which document should they create?
Answer: The Resource Breakdown Structure (RBS), which may be divided between the team management plan (for personnel) and the physical resource management plan (for equipment and materials).
PMI Exam Traps
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Trap: Confusing RBS with WBS (Work Breakdown Structure) Reality: WBS decomposes project deliverables and work; RBS decomposes resources by category and type
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Trap: Assuming RBS is only for physical resources Reality: RBS includes both team resources (personnel, roles) and physical resources (material, equipment), potentially split across two plans
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Trap: Thinking RBS is a standalone document Reality: RBS is a component of the resource management plan, which is itself part of the project management plan
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Trap: Confusing RBS with OBS (Organizational Breakdown Structure) Reality: OBS shows organizational units and reporting relationships; RBS shows resource categories and types hierarchically
Important PMI Connections
| Related Concept | Relationship Type | Exam Attention Point |
|---|---|---|
| Work Breakdown Structure (WBS) | Used in conjunction with | RBS + WBS together enable detailed work and resource planning, monitoring, and control |
| Resource Management Plan | Component of | RBS is documented within this plan, which covers acquisition, allocation, monitoring, and control |
| Team Management Plan | Contains part of RBS | Personnel and role portions of RBS may reside here |
| Physical Resource Management Plan | Contains part of RBS | Material and equipment portions of RBS may reside here |
| Organizational Breakdown Structure (OBS) | Complementary structure | OBS shows who does the work; RBS shows what resources are needed |
Quick Review Questions
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A project has 50 team members and requires specialized equipment across 3 work packages. Which breakdown structure would best help organize these resources hierarchically?
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The RBS can be divided between which two plans according to project specifics?
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At which point in the RBS hierarchy is the resource information considered detailed enough to be used with the WBS?
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What are the four main resource categories shown in the sample RBS from PMBOK v8?
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A project manager needs to track resource availability considering experience levels and geographic locations. Which plan would contain this information alongside the RBS?
PMBOK v8 Reference
Section 4.2.3 - Develop Project Management Plan (Resource Management Plan component) Section 4.4 - Resource Management Figure 4-4 - Sample Resource Breakdown Structure