Mapping water, sanitation, and hygiene achievements to prosperity, stability, and resilience outcomes

„ This WASH systematic map is 3ie’s first study employing an outcome-to-outcome mapping approach and identifies 279 studies examining the question: are WASH outcomes linked to higher-level development outcomes? „ Among WASH outcomes, we found concentrations of research on increased access to enhanced drinking water services and increased access to sanitation/hygiene facilities, products, or services. Among high-level outcomes, we found concentrations of research on education, livelihoods, public perceptions of institutions, women’s empowerment, and pollution. We also found a concentration of research at the intersection of expansion of enabling environments for menstrual health and hygiene achievements and education, primarily focused on school absence. „ The map reveals research gaps on increased uptake of safe food-hygiene practices among WASH outcomes, and on conflict and climate-linked resilience outcomes among high-level outcomes. „We identified relatively few impact evaluations and a lack of quality systematic reviews, indicating opportunities for more causal research and highquality synthesis work. The COVID-19 pandemic brought a renewed focus to water, sanitation, and hygiene (WASH) issues, as it highlighted that there was still substantial work needed to be done in this sector. Though there has been significant progress in understanding the impacts of WASH on human health, less is understood about the broader implications it may have on higher-level development outcomes, such as prosperity, stability, and resilience. Understanding the link between achieving WASH outcomes and higherlevel outcomes is needed to better understand the far-reaching impacts of delivering WASH services.