Access to safe water, sanitation, and hygiene (WASH) is a fundamental human right and a critical component of public and environmental health. Inadequate access to WASH facilities and practices can give rise to preventable diarrheal and waterborne diseases, which can have severe consequences on individuals' health and well-being. This is especially true in low- and middle-income countries such as India. To address these issues, the S.M. Sehgal Foundation identified water quality and hygiene needs in Bihar, India, and thus launched a behavior change intervention called "WASH for Healthy Homes." The intervention aimed to promote the use of silver-ceramic pot filters and safe handwashing practices in five communities of the Vaishali District. While behavior change is a common approach to address WASH issues, evaluating the outcomes of such interventions is crucial for determining the most effective strategies and conditions under which they can be successful. Therefore, this study assessed the effectiveness of the WASH for Healthy Homes intervention and identified factors that influenced its success. A mixed methods approach was utilized that combined statistical analyses of pre- and post-intervention survey data with a thematic analysis of interview and focus group discussion data. Results demonstrated that the intervention was successful in increasing the adoption of the silver-ceramic pot filter and overall safe handwashing practices within the study communities. Success of the WASH for Health Homes intervention was facilitated by participants' health concerns, trust in the field coordinator and social peers, the aesthetic appeal of the treated water, and repeated intervention messaging. However, adoption of intervention behaviors was hindered by several factors, including economic barriers, gender roles in decision-making, the effects of children and elderly in the household, and low attendance during intervention sessions. The research findings provide valuable insights that can help nonprofits better design and execute behavior change interventions, especially in the face of increasing WASH challenges. / Master of Science / Access to safe water, sanitation, and hygiene is a basic human right and critical for human health. Unfortunately, many people, especially those in low- and middle-income countries like India, lack adequate access to these facilities, leading to waterborne diseases and other health problems. To address this issue, the S.M. Sehgal Foundation launched a behavior change program called "WASH for Healthy Homes" to promote the use of water filters and safe handwashing practices in rural Bihar, India. To determine the success of the intervention and identify factors that influenced its effectiveness, this study used a variety of methods including statistics, interviews, and focus group discussions. Results showed that the program was successful in increasing the adoption of the filter and safe handwashing practices. Success was due to participants' health concerns, trust in the field coordinator and their peers, the aesthetic appeal of the filtered water, and repeated messaging. However, there were also barriers to adoption, such as economic barriers, gender roles, and low attendance during intervention sessions. These findings are important for nonprofits to better design and execute behavior change interventions in the face of growing WASH challenges.