The document discusses validations in SAP Project System (PS) and provides answers to various questions on the topic. It includes details on when validation points 110 and 120 are triggered, how to validate user-defined fields in the work breakdown structure (WBS), and how to use user exits for validations. The document also covers how to make the full WBS description appear in hierarchical reports, how to put checks before setting the system status to "Technically Completed", and how to create documents in PS that link to URLs instead of files on a document management system.