Human security in the Hindu Kush Himalaya (HKH) region confronts unprecedented challenges as climate change fundamentally alters the environmental foundations upon which nearly two billion people depend. The study area, spanned four countries of the HKH region, namely Afghanistan, India, Nepal, and Pakistan, which provide water resources through ten major river basins and harbour some of the world’s most climate-vulnerable populations. This assessment examines human security challenges across the four focus countries which represent diverse vulnerabilities and adaptive capacities. The assessment applied an integrated framework developed to analyse how climate impacts cascade across interconnected food, water, and energy systems to create compound threats exceeding individual sectoral impacts