This report examines the relationship between poverty, access to water and sanitation, and the nutritional status of children—specifically, child stunting. Over the past decade and a half, Pakistan saw a very substantial decline in poverty. Commensurate with this, access to water supply, sanitation, and hygiene (WASH) infrastructure expanded, open defecation more than halved, and dietary diversity improved, even among the poorest. Health behaviors and access to primary curative health care also improved. Yet, surprisingly, two critical markers of child health: rates of diarrhea and stunting have shown virtually no signs of a decline. The report focuses on this apparently anomalous set of facts.