Work that has been done in low-income countries to build health systems that can respond to AIDS and TB (as well as other acute and chronic diseases) shows that with adequate resources, we can improve care delivery, sharply reducing morbidity and mortality. More than four decades after one U.S. Surgeon General reportedly declared it “time to close the book on infectious diseases,” drug-resistant pathogens have diminished the effectiveness of once-potent therapies. 1 In the past three decades, newly described pathogens, including the human immunodeficiency virus (HIV), the severe acute respiratory syndrome (SARS) virus, and the H1N1 influenza virus, have caused pandemics, while old scourges from tuberculosis to cholera have persisted or resurged. Simultaneously, rising life expectancy and rapid social change have led to an increasing burden of chronic diseases for which we have effective therapies but inadequate innovation for delivering them efficiently to . . .