Local strategies to manage climate variability are key to adapting to climate change in the long term. We investigate how local adaptive strategies are socially organised through a study of Øystre Slidre, a Norwegian mountain farming community operating close to the climatic margins. Farmers actively use informal social relations in accessing equipment and labour in order to secure production and quality of life. The importance of such relations in managing climate variability persists even with a dramatic shift towards larger scale production, increasing formalisation and economic diversification. Despite social innovations and adaptations such as the re-forming of social relationships and institutions, the concurrent reduction in the number of people involved in farming may be putting the flexibility of social networks and practices of collaboration under pressure, potentially undermining adaptive capacity to climate change. Future research and policy need to focus on ensuring social innovation in the social organisation of adaptation.