Led by the Bill & Melinda Gates Institute for Population and Reproductive Health at Johns Hopkins Bloomberg School of Public Health, The Challenge Initiative is a “business unusual” platform that empowers local governments to rapidly and sustainably scale up best-practice health interventions to benefit urban poor communities. The Initiative builds on the demonstrated success of the Bill & Melinda Gates Foundation’s Urban Reproductive Health Initiative (URHI)—a 2010-2016 effort to improve the reproductive health of the urban poor in India, Kenya, Nigeria, and Senegal.