In December 2006, in response to the preventable threats posed by poor sanitation and hygiene, the Water and Sanitation Program (WSP) launched Global Scaling Up Handwashing and Global Scaling Up Rural Sanitation1 to improve the health and welfare outcomes for millions of poor people. Local and national governments implement these large-scale projects with technical support from WSP. Handwashing with soap at critical times-such as after contact with feces and before handling food-has been shown to substantially reduce the incidence of diarrhea. It reduces health risks even when families do not have access to basic sanitation and water supply. Despite this benefit, rates of handwashing with soap at critical times are very low throughout the developing world. Global Scaling Up Handwashing aims to test whether handwashing with soap behavior can be generated and sustained among the poor and vulnerable using innovative promotional approaches. The goal of Global Scaling Up Handwashing is to reduce the risk of diarrhea and therefore increase household productivity by stimulating and sustaining the behavior of handwashing with soap at critical times in the lives of 5.4 million people in Peru, Senegal, Tanzania, and Vietnam, where the project has been implemented to date. In an effort to induce improved handwashing behavior, the intervention borrows from both commercial and social marketing fields. This entails the design of communications campaigns and messages likely to bring about desired behavior changes and delivering them strategically so that the target audiences are “surrounded” by handwashing promotion via multiple channels. One of the handwashing project's global objectives is to learn about and document the long-term health and welfare impacts of the project intervention. To measure magnitude of these impacts, the project is implementing a randomized-controlled impact evaluation (IE) in each of the four countries to establish causal linkages between the intervention and key outcomes. The IE uses household surveys to gather data on characteristics of the population exposed to the intervention and to track changes in key outcomes that can be causally attributed to the intervention. The objective of the IE is to assess the effects of the handwashing project on individual-level handwashing behavior and practices of caregivers. By introducing exogenous variation in handwashing promotion (through randomized exposure to the project), the IE will also address important issues related to the effect of intended behavioral change on child development outcomes. In particular, it will provide information on the extent to which improved handwashing behavior contributes to child health and welfare. The primary hypothesis of the study is that improved handwashing behavior leads to reductions in disease incidence, and results in direct and indirect health, developmental, and economic benefits by breaking the fecal-oral transmission route. The IE aims to address the following research questions and associated hypotheses: 1. What is the effect of handwashing promotion on handwashing behavior? 2. What is the effect of improved handwashing behavior on health and welfare? 3. Which promotion strategies are more cost-effective in achieving desired outcomes? (The above excerpt is taken from: Scaling Up Handwashing Behavior: Findings from the Impact Evaluation Baseline Survey in Vietnam Claire Chase and Quy-Toan Do November 2010) The report is attached.