The Koshi river basin is shared between China, Nepal and India and is one of the key trans-boundary river basins in the Hindu-Kush Himalayas (HKH). The basin drains an area of about 88,000 km2 and is a river system with a high potential for investments in hydropower development as well as irrigation in the downstream areas. In addition the basin contains important ecosystems and protected areas which provide a range of biodiversity and related ecosystem services and sustain livelihoods. The basin is home to over 40 million people with agriculture as the dominant activity. However, the diverse topography, young geological formations, degree of glaciation and monsoon system make the basin particularly prone to water-related hazards like extreme flooding and landslides. Droughts are also experienced in the rain-fed tributaries of the basin during the dry season. Urbanisation and floodplain encroachment have also added pressures on the water bodies and ecosystems of the basin. Climate change will likely exacerbate these pressures with consequences for seasonal water availability, and food and energy security, highlighting the need for appropriate water management and disaster risk reduction strategies. A river basin approach, through the application of integrated water resources management (IWRM) principles, is essential to address the trans-boundary nature of many of these multifaceted issues. A conceptual framework for addressing these challenges within an integrated water and land resources management perspective for the Koshi basin is presented in this paper.