This document provides guidance on work breakdown structures for organizations undertaking project or programme management, as well as uses and benefits for portfolio management. This standard is applicable to any type of organization, including public or private and any size of organization or sector, as well as any type of project and programme in terms of complexity, size, or duration. This document provides descriptions of applicable terms and definitions, concepts, characteristics, benefits, uses, integration and relationships in regard to work breakdown structures. This document does not provide guidance on the use of processes, methods, or tools in the practice of developing and using a work breakdown structure.