This case study seeks to understand how the Lagos Eko Secondary Education Project (Eko Project) in Nigeria tailored international best practices to leverage impact through education sector reforms in Lagos State’s public secondary school system. As the economic center of Nigeria and a financial powerhouse in West Africa, Lagos State has benefitted from significant education sector reforms initiated by reform-minded state officials. Demand for education has always been high in the state, but for many years the quality of secondary schools lagged behind. Infrastructure deficiencies, shortages in learning materials, and scarce opportunities for teachers’ professional development compounded these problems. In this context, a new governor took office in 2007 on a platform that placed education sector reforms at the top of the agenda. The governor recruited a topnotch program coordinator and sought the World Bank’s support to design and launch the Lagos Eko Secondary Education Project in 2009. Drawing on international best practices, the project set out to support improved learning outcomes through school development grants, performance-based incentives for schools, public–private partnerships for technical colleges, teacher training and mentoring, and more reliable performance measurements through improved standardized testing of learning achievement. The Eko Project, which is set to close in June 2016, has worked steadfastly toward achieving its development objective of improving the quality of public junior and senior secondary education in Lagos State, despite a significant drop in test scores in 2014—a setback that accentuated a national-level trend. This case study explores how the Eko Project tailored international best practices to leverage impact in Lagos State’s public secondary education system and assesses how the project resolutely responded to the challenges posed by the drop in test scores. Using a qualitative methodology based on semistructured interviews and focus-group discussions, the case study concludes that a proactive approach in a moment of committed political leadership from top to bottom—together with targeted program design, thoughtful adaptation of international experience, and efforts to foster a culture of performance— created the conditions for meaningful and sustainable reform, despite the challenges posed by demographic pressures and funding constraints.