The INCOSE Detroit Chapter recently had me present a talk on ISO/IEC/IEEE 29148 Systems and Software Engineering – Life Cycle Processes – Requirements Engineering, Conceptual Modeling, Controlled Vocabularies, and Property-Based Requirements (PBR) using the Object-Constraint Language (OCL). The presentation addresses a very small, yet critically important (IMHO) aspect of the ISO standard; explicit documentation of the vocabulary of the set of requirements. A modeling practice that is rarely encountered in my experience and not explicitly supported by either the UML or SysML OMG standards. The OMG’s SBVR standard does address vocabulary modeling, an approach pragmatically employed by the OMG UML Testing Profile V2 standard. Two exemplars were discussed, both are available in the ‘Documents’ area of this site. The model{DRAFT} UML Testing Profile v2.1 May 2020 addresses the topic of conceptual domain modeling and vocabulary modeling and the Property-Based Requirement with OCL.zip model addresses the topic of PBR using OCL. The INCOSE chapter recorded the presentation and it is available on YouTube @< https://www.youtube.com/watch?v=luXMQ0sQoFU&list=Property-Based-GNA24kEmAMiW_gB9VpLthBKy > if you have an interest. NOTE: The methodology employed is mandraulic (intensive manual effort), especially creating the hyperlinks between model elements and the PBR’s natural language text. That said, these links between the model element and the PBR text are captured in the metadata of the PBR (see – Tags::«ElementReferenceInText»). This can provide an aspect to requirement traceability not offered without using this method. The effort MAY be justified by the traceability risk established for the project. Perhaps this method is only justifiable for a limited number of the requirements in a requirement specification set.