A resource breakdown structure (RBS) is a type of chart that shows which resources are needed in the project and allows you to group the resources by project phase or other attributes. A resource is anything that is required to perform the project activities, such as human resources, equipment, materials, facilities, etc. A RBS is a hierarchical representation of the resources, where each level represents a category or a subcategory of resources. A RBS helps to plan, allocate, monitor, and control the resources for the project. A RBS also helps to identify the dependencies and constraints among the resources, as well as the potential risks and opportunities related to the resources. References: CBAP / CCBA Certified Business Analysis Study Guide, chapter 6, page 237; CBAP Sample Questions, question 237.