Upland Japan suffers from extreme depopulation, aging, and loss of agricultural, economic, and social viability. In addition, the absence of a successor generation in many marginalized hamlets endangers the continuation of local knowledge associated with upland agricultural livelihoods and severely limits the prospects of rural revitalization and development. Resettlement by incomer organic farmers represents an opportunity to both pass on valuable local knowledge and rejuvenate local society. Survey and interview data are used to explore the knowledge dynamics at play in (...) upland Japan between local and incomer organic farmers. Using a “knowledge culture” framework, socio-cultural and symbolic barriers and spatial conditions limiting local knowledge exchange are identified and analyzed. Despite a number of reasons to suggest affinity and natural alignment toward knowledge sharing, each group’s ideas of “legitimate knowledge” and acceptable behavior have contested the field of communication and confused the negotiation process. Building on previous studies of farmer’s knowledge networks, examples in this study suggest that negotiation between knowledge cultures can be facilitated by both active means and intrinsic factors, and be derailed because of physical and temporal symbolic references. The degree to which locals and incomers collaborate and identify with each other as stakeholders with a common future may determine the extent to which local knowledge, especially local knowledge from past agricultural regimes, can play a role within upland endogenous development. (shrink)