India is home to one-third of the global population without access to improved sanitation, with widespread open defecation and high rates of diarrhoeal mortality. To address this issue, a cluster-randomized controlled trial was conducted in 100 villages in Odisha, where intervention villages received latrine construction alongside behavior-change promotion efforts, while control villages received no intervention. The primary outcome measured was the prevalence of diarrhea in children. Despite an increase in latrine coverage in intervention areas, the study found no significant reductions in child diarrhoea, soil-transmitted helminth infections, or indicators of malnutrition. These results suggest that simply providing sanitation infrastructure is not sufficient to improve health outcomes. Effective sanitation programs must also achieve high levels of uptake, consistent latrine use, and meaningful reductions in environmental exposure to fecal contamination.