The presentation focuses on the importance of modeling uncertainty in systems engineering to enhance design, performance, and risk management. It introduces the Precise Semantics for Uncertainty Modeling (PSUM), a new OMG standard that defines concepts like uncertainty, precision, and belief. While PSUM provides a metamodel, it requires integration with popular modeling approaches such as SysML and UAFML. The discussion explores extending these standards, including SysML V2, to incorporate uncertainty modeling, with practical examples. By linking uncertainty to system measurements, risks, and precision, engineers can better address unknowns, improve designs, and manage operational challenges. The presentation highlights how modeling uncertainty should be integral to both the design and operation processes, ultimately improving system reliability and performance under various scenarios and conditions.