Development necessitates specialised communication involving multiple actors at many levels, especially in Global South contexts. However, this communication is hindered because the discourse, concepts and terminology of development developed in the West are introduced into communities in many parts of the world, including Vietnam, with little evidence that they are being understood or used as intended. Problematic translations of development concepts could have significant real-word impacts on the multidirectional communication between key stakeholders involved in development, impede policy-making and prevent the implementation of development initiatives at local levels. This interdisciplinary PhD project—combining perspectives from Translation Studies and Development Studies with insights gained from real-world development practice—addresses the problem space of communication and mutual understanding in development settings to answer the following overall research question: What role(s) do translation and terminology have in development practice and policy in Vietnam? This research was undertaken using a methodology that combined a case study approach with an ethnographic orientation. Data from in-depth, online interviews with 18 development stakeholders in Vietnam were triangulated with analysis of a 1.1 million-word corpus of development texts, the researcher’s autoethnographic accounts, grey literature, and a specially-designed workshop for stakeholders. Findings suggest that translation of key development concepts in Vietnam is problematic with under-recognised impacts on development practice and policy, and this situation could be improved through policy interventions, better tool use, new translation workflows and practices, and greater shared learning. Overall, analysis in this study suggests that translation and terminology are used by various stakeholders in Vietnam as important enablers to local participation and ownership, achieve meaningful development outcomes through local empowerment and contribute to the decolonisation of development. Keywords: Translation, terminology, development practice, development policy, Vietnam, interdisciplinarity, vernacular knowledge, practice theory.