Since 1998, the California Independent System Operator (CAISO) has used the PI System to reliably manage one of the world’s largest power grids and transparently operate its wholesale energy market. With climate change challenges and increasing renewable energy and distributed energy resources, CAISO continues to transition by leveraging PI Infrastructure to meet the industry needs. This presentation will review CAISO’s PI System journey over the last 20+ years. It will discuss the migration of thousands of PI ProcessBook displays to PI Vision and describe how PI AF has been used to drive analysis enabling situational awareness. Essential to this effort is the ability to securely share data and operational intelligence with more than sixty external entities, including 40+ RC-Reliability Coordinators, 20+ EIM-Energy Imbalance Markets, NERC (North American Electric Reliability Corporation), FERC (Federal Energy Regulatory Commission) and WECC (Western Electricity Coordinating Council).