U.S. social programs, set up to address important problems, often fall short by funding specific models/strategies ("interventions") that are not effective. When evaluated in scientifically-rigorous studies, social interventions in K-12 education, job training, crime prevention, and other areas are frequently found ineffective or marginally effective. Interventions that produce sizable, sustained effects on important life outcomes tend to be the exception. The Top Tier Evidence Initiative seeks to assist policy officials in identifying interventions meeting the Congressional Top Tier evidence standard, defined in recent legislative provisions as "well-designed randomized controlled trials [showing] sizeable, sustained effects on important outcomes." Between 2002-2008, New York City created Small Schools of Choice (SSCs) to replace large public high schools with graduation rates below 45 percent located in disadvantaged communities. The schools were newly created through a competitive process, in which the city invited applications from prospective school leadership teams. Additional SSC features include: (1) new principals and teachers (as opposed to transfers from a large high school that the SSC replaced); (2) start-up funding from the city's Department of Education and philanthropic organizations (such as the Bill and Melinda Gates Foundation); (3) assistance with leadership development, staff hiring, and program start-up from intermediary organizations (such as New Visions for Public Schools); and (4) partnerships with local businesses or nonprofit organizations that offer students learning opportunities inside and outside the classroom. This evidence summary provides a detailed description of the Small Schools of Choice (SSCs) intervention. The Panel finds that this intervention meets the "Near Top Tier" evidence standard. Evidence of effectiveness, discussion of study quality, summary of intervention's benefits and costs, and benefits to society are also discussed.