The role of faith-based organizations in meeting the most pressing needs in America's poorest neighborhoods has been the subject of national debate over the past several years. However, few reports have carefully examined these organizations' performance. Mustering the Armies of Compassion in Philadelphia takes a detailed look at a group of faith-based organizations running a literacy program, Youth Education for Tomorrow (YET). Mustering examines the programs' start-up, relatively consistent classroom results, and their many reactions to partnership with a secular organization. Ultimately, the YET Center program shows that with a clear model and sufficient support and oversight, a large and diverse group of independent faith-based organizations can collectively provide a demonstrably effective service.