Purpose: To explore smallholder farmers' decision-making for climate adaptation in the mountainous areas of Central Vietnam, in order to target extension efforts. Design/Methodology/Approach: The study focussed on Th?a Thiên-Hu? province, utilising commune meetings, key informant interviews and a survey of 302 households as data collection methods. Findings: Smallholder farmers in the study region are undertaking short-term, reactionary adaption. In particular, ethnic minority farmers are not following a full range of steps in their decision-making, instead moving from the identification of climate impacts to implementing (other farmers') actions at scale. Practical implications: Short term adaptation and reliance on other farmers suggests that bonding social capital in the study sites is favourable but development of bridging and linking social capital through a greater network of agricultural advisory services could improve farmers' perceptions of climate risk and subsequent adaptation strategies. Theoretical implications: The study adds to the literature on farmers' decision-making for climate adaptation. Specifically, it provides insight regarding extension programme design, based on data of farmers' adaptation decision-making. Originality/value: Much has been written on farmers' adaptation to climate change. This paper focuses explicitly on the steps of that decision-making for the purpose of targeting extension programmes to support sustainable development.