This paper evaluates the determinants and impact of adopting the metal silo - a postharvest storage technology for staple grains - which was disseminated by the Swiss Agency for Development and Cooperation (SDC) from 1983 to 2003 in four Central American countries. The aim of the SDC program was to diminish small farmers’ postharvest losses by facilitating the manufacture and dissemination of metal silos and thereby to improve regional food security. Our empirical analysis is based on a unique data set obtained from a survey of 1,600 households from El Salvador, Guatemala, Honduras and Nicaragua. We employ a double-hurdle model to identify factors that contributed to the adoption of metal silos. We use tobit and standard regression models to assess the impact of adopting the metal silo on the food security and well-being of the considered households. Our estimation results show that both the household demand for metal silos and the impact of their adoption varied across the four considered countries. This finding points out the relevance of regional policies for the adoption of a technology, as well as its impact. Additionally, our results indicate that - in addition to the household self-sufficiency in maize - the main determinants of adoption were household socio-economic characteristics such as age, land ownership, completion of a training course and quality of basic infrastructure. Finally, when considering a group of economic and social indicators of household well-being, we found that, compared to the silo non-adopters, the adopter-households experienced a significantly higher improvement in their food security and well-being from 2005 to 2009.