Dairy animals are an important source of income, food and nutritional security at the household level, and improvement in the production and productivity of dairy animals substantially improves the well-being of smallholder farmers. Like other developing countries, dairy animals are key for rural livelihoods in Nepal but often suffer from mastitis, a production disease causing economic losses to farmers, challenges to the dairy processing industry and possible health hazards to consumers. Studies show that the prevalence of sub-clinical mastitis in Africa and Asia exceeds 50%, threatening farmers, dairy processors and consumers. A study was done in Nepal by Heifer International Nepal to develop a technology package to control mastitis in dairy animals. This project was carried out with financial and technical support from the Livestock Systems Innovation Lab at the University of Florida, and in partnership with the Department of Livestock Services and Himalayan College of Agricultural Sciences and Technology. The technology package consisted of (1) identifying knowledge gaps; (2) developing good husbandry practices, including mastitis detection and control technologies; and (3) training of technicians and farmers. The package was applied in the mid-western region of Nepal. Six months after implementation, a reduction in sub-clinical mastitis prevalence was observed in dairy cows (55% at baseline to 28%, n = 432) and buffalo (78% at baseline to 18%, n = 216). These positive study outcomes strongly suggest that the mastitis technology package can be scaled among smallholder farmers across and beyond Nepal to control mastitis in dairy animals.