Large-scale, legacy education systems continue to serve the vast majority of K-12 students nationwide. And system leaders today operate in a fundamentally different environment — one shaped by rapid technological change, shifting enrollment patterns, and growing demands for personalization. This session explores how established systems are responding with urgency and creativity, and how leaders are embracing institutional evolution as a catalyst for innovation. How can these systems measure what matters? How can they use flexible funding tools to accelerate learning? What operational shifts are required to thrive? If we want vibrant educational systems within a pluralistic ecosystem, we must surface the strategies that are working and scale them with intention.