Environmental migration is not a new phenomenon. Since time immemorial, environmental stressors have induced people to migrate. What is new is the growing understanding of the wider linkages between climate change and the environment and migration, and the implications of this for migration. A growing consensus suggests that migration is an important strategy in reducing vulnerability to environmental and non-environmental stressors through livelihood diversification. Although labour migration has long been a key livelihood strategy in mountain communities, there are few data available and little is known about the actual influence of environmental stressors on migration behaviour in mountain areas, or the impact of remittances on the ability of households to adapt. This report presents the results of a regional study of labour migration in communities affected by water hazards (droughts and floods) in selected mountain and hill communities in China, India, Nepal, and Pakistan. The findings suggest that for many households in the Hindu Kush-Himalayas labour migration is a potential strategy for adaptation to the impacts of water hazards.