Co-authored by Bryan Hassel and Amy Way as a chapter in Frederick Hess’s 2005 volume With the Best of Intentions: How Philanthropy is Reshaping K-12 Education (Harvard Education Press). The chapter aims to shed light on the question: How extensive is choice-related philanthropy in the United States? By evaluating the top 50 donors in K-12 education for the extent and nature of their financial support for school choice we determined a successful movement will focus on creating high quality options for students and finding ways to reach the scale needed to make up a significant portion of the educational market. To achieve this we need a broader set of donors willing to enter into this controversial movement.