School-based handwashing programs are challenging to establish and sustain, especially in low-resource settings. This qualitative study described teacher perspectives associated with implementing and sustaining a handwashing program in primary schools participating in the Nyando Integrated Child Health and Education (NICHE) project. Structured key informant interviews were conducted with teachers. Prevalent concepts and themes were grouped into themes and topic areas using an iterative, open coding approach. Forty-one teacher respondents reported favorable expectations and benefits of handwashing programs. The importance of available resources (e.g., reliable water) was cited as a primary concern. Other challenges included time and personal or institutional financial commitment necessary to ensure program sustainability. Handwashing programs in low-income, rural schools, where infrastructure is lacking and "student ambassadors" extend the intervention to the surrounding community, hold great promise to improve community health. Teachers must have adequate support and resources to implement and sustain the programs.