Over the past one hundred years, systems of free, public education have been powerful engines of change, propelling societies to realize greater potential socially and economically and socially. We are at a moment where education is again needed to help address the significant and complex challenges facing our respective nations and the planet. Educators are a critical part of engineering that paradigm shift. There is a need to fundamentally rethink the structure of how we train and support educators, which can unlock their potential to be more effective agents of change, thereby promoting greater sustainability and well-being in students, among fellow educators, and on the broader system itself. In this chapter, we tell the story of how our system of education is currently not working for kids or most of the adults in it; we set the context by examining megatrends for what's currently impacting education; we lay out the logic for why rethinking how adults in the system learn is a priority with an example of what the future of educator learning could be. In conclusion, this chapter makes an argument for why rethinking professional learning has the power to transform education.