A wide range of holistic frameworks are used to assess the sustainability of agricultural policies and programs, but much of the existing research tends to overlook the socio‐cultural and governance dimensions of sustainability. This article aims to address those gaps by comprehensively assessing the environmental, economic, social, and political dimensions of sustainability. We use a case study of irrigation policies for agricultural expansion that target the Pagar Alam upland region in Indonesia. The assessment reveals opportunities and threats from the policy that affect the sustainability of upland landscapes and communities. By overly focusing on productivity goals while ignoring other sustainability criteria, the policy generates risks that threaten existing sustainable development pathways. To achieve positive policy outcomes, Indonesia needs to reconcile its national food production goal with local development goals. Lastly, to optimise policy outcomes, agri‐sustainability research should apply comprehensive approaches that simultaneously address multiple sustainability dimensions.