The PI System assists with collecting, archiving, and visualizing real-time operational data across multiple NYISO functions (e.g., Managing NY Grid Reliability and Wholesale Energy Markets). This presentation reviews the evolution of PI at NYISO, from its early role as a data historian to a broader enterprise platform supporting operational awareness and data-driven decision making. Topics include a brief history of PI deployment patterns, visualization enhancements, the use of emerging PI System technologies, and a discussion on potential future enterprise upgrades.