The effects of global environmental change, including coastal flooding, reduced rainfall in drylands and water scarcity, will almost certainly alter patterns of human migration. Conventional narratives usually cast these displacements in a negative light, with many millions of people forced to move, and tension and conflict the result. Our study suggests that the picture is not so one-sided. The study, the UK government's Foresight report on migration and global environmental change, examines the likely movement of people within and between countries over the next 50 years. It contends that, although environmental change will alter an already complex pattern of human mobility, migration will offer opportunities as well as challenges. The greatest risks will be borne by those who are unable or unwilling to relocate, and may be exacerbated by maladaptive policies designed to prevent migration. It is time for a fresh discourse - and fresh research - on migration in relation to global environmental change."