A major barrier to achieving sustainable diets is the lack of clearly defined and agreed upon intervention points that will positively influence multiple sectors of the food system. There is an urgent need to understand what policy approaches and interventions will most effectively enhance the sustainability of diets in rapidly urbanizing low- and middle-income countries. To address this need, this work combines the input of diverse stakeholders and analysis of existing datasets to develop a conceptual framework for sustainable diets that is locally relevant to Vietnam using a process that is generalizable to other developing countries. The resulting framework includes 235 unique, measurable indicators within eight domains: (1) food production, (2) food processing and distribution, (3) food loss and waste, (4) food access and consumption, (5) food and water safety, (6) nutrition, (7) sociopolitical context, and (8) environmental impact. This conceptual framework was employed in a participatory workshop that brought together 50 Vietnamese stakeholders from diverse areas of expertise to identify and prioritize specific metrics for measuring sustainable diets. Based on the results of the stakeholder workshop, expert interviews, and characterized datasets, a comprehensive set of minimum metrics for each domain was produced and key leverage points that are likely to have an impact across multiple sectors were identified. These leverage points include food quality and safety, agricultural chemical usage, food waste, and water management. The analysis is expected to contribute to evidence-based policymaking in Vietnam to cultivate more sustainable diets.