This International Standard specifies processes, requirements and recommendations for the breakdown of project management structures, collectively called project breakdown structures, in terms of the various specification (i.e. requirements), functional, product, work, cost, business and organizational breakdown structures that are established and implemented to contribute to the success of a space programme, which is often composed of one or more projects. It is intended to complement and supplement similar project breakdown structure processes, requirements and recommendations contained within ISO 14300-1, which serves as a higher tier International Standard for this International Standard and for such other space systems and operations International Standards that require formal project breakdown structures. This International Standard specifies the various types of project breakdown structures and gives processes, requirements and guidance concerning the composition of these breakdown structures. This International Standard is applicable to project breakdown structures for a project, including at the top level of a programme, i.e. level 0, as indicated in ISO 14300-1. It is intended to be used either by an independent developer as a partial basis for programme processes or as a basis for an agreement between a supplier and a customer. This International Standard also provides descriptions of the kinds of project breakdown structures that are commonly useful in contributing to the success of a space project. Other project breakdown structures not described in this International Standard also often contribute to the success of a space project.