The Asia-Pacific region is facing the challenges of securing water, energy and food. These challenges are intensifying due to economic growth and transformation, population growth, unsustainable land and resource use, changing lifestyles and climate change. As they are interconnected, to avoid major trade-offs these challenges need to be addressed through a nexus approach that considers water, energy and food as an integrated system.The water-energy-food nexus (WEFN) approach can play an important role in harnessing the synergies that exist between Sustainable Development Goals (SDGs) 2, 6 and 7, securing win-win solutions where possible, as well as in minimising potential trade-offs. To fulfil this role, better understanding based on scientific evidence of the linkages between SDG 2, SDG 6 and SDG 7, and their targets, is required.A number of common issues related to water, energy and food security have been identified in developing Asian countries. In the case of Bangladesh, India and Vietnam, these include: (i) inefficient use of water resources for irrigation, mainly driven by subsidised energy supply for irrigation water pumping; (ii) high dependency on thermal power plants, leading to increasing demand for water as a coolant by the energy sector; (iii) deteriorating water quality due to the discharge of untreated domestic and industrial wastewater, which threatens food safety and security, and rising costs and energy inputs for water treatment. Each of these issues affects more than one sector and can best be addressed through a WEFN approach.In developing Asian countries, the introduction and operationalisation of the WEFN approach faces many challenges including: (i) absence of institutional coordination; (ii) influence of political priorities on decisions rather than use of scientific knowledge to shape the decisions; (iii) lack of capacity to understand interlinkages between sectors; (iv) lack of multi-stakeholder engagement in planning and decision-making processes; and (v) lack of incentive mechanisms and adequate finance to support the approach.There is a strong need to establish enabling frameworks for promoting and governing the WEFN. These frameworks should be based on a continuous back-and-forth cycle between the generation of scientific evidence-based knowledge, the preparation of strategic guidelines, the identification of the means of implementation and practical nexus-oriented actions.