The PSP is organized around the primary products of the project (or the expected results) in the place of work necessary to manufacture the products (planned actions). Since the intended results are the desired objectives of the project, they constitute a relatively stable set of categories in which the costs of the proposed actions that are necessary to achieve them can be met. A well-designed PSP makes it easy to assign each project activity to a single terminal element of the PSP. In addition to its costing function, the PSP also helps to categorize requirements from one level of system specification to another, for example. B a cross-reference matrix that has functional requirements on high or low design documents. The PSP can be displayed horizontally as a structure or vertically as a tree (such as an organigram). A work account (SOW) is a document used regularly in the field of project management. This is the narrative description of a project`s work requirement.  It defines project-specific activities, delivery items and schedules of a supplier providing services to the customer. THE SOW generally contains detailed requirements and prices with standard regulatory and governance conditions. This is often an important corollary of a master service contract or a bid request (RFP). An important design principle for work-sharing structures is called the 100% rule.
 It was defined as: Note that, in many cases, the declaration of work is a binding contract.  Corporate framework agreements or consulting/training service contracts defer specific elements of the contract, which are addressed in individual work declarations. The master service contract serves as a master`s contract for the conditions for potentially several SOWs. It sometimes refers to the volume of work. If a project is implemented by contract. B, the domain instruction that is part of it can be used as SOW, because it also clearly and concisely describes the work of the project.  A work structure allows subordinate costs for tasks, materials, etc. to be grouped into higher “higher” tasks, etc.
For each element of the work structure, a description of the task to be performed is generated.  This technique (sometimes called a system structure) is used to define and organize the entire project.