"Climate change is damaging people?s lives today. Even if world leaders agree the strictest possible curbs on greenhouse gas (GHG) emissions, the prospects are very bleak for hundreds of millions of people, most of them among the world?s poorest. This paper puts the dramatic stories of some of those people alongside the latest science on the impacts of climate change on humans. Together they explain why climate change is fundamentally a development crisis. The world must act immediately and decisively to address this, the greatest peril to humanity this century...As this paper was being prepared in late May 2009, Cyclone Aila hit Bangladesh and East India. The headline news was of deaths (more than 200, including many children), of 750,000 people made homeless, of landslides, floods, water contamination, threat of disease, the devastation of food crops and livelihoods – of 3.6 million people ?affected?. The Satkhira district in Bangladesh was hit hard. Just weeks before Aila, Oxfam held the first of its international Climate Hearings in villages there. More than 12,000 people gave their personal experiences of climate change, many saying that the sea level was rising, the tides were higher, and salt water was steadily encroaching on their land. When it hit, Aila coincided with yet another unusually high tide and storm waters breached the embankments. Before Aila, at the hearings, Baburam Mondal described how the encroachment of salt water had wiped out his mangoes and coconuts. Ashoke Kumar Mondal said he had lost his livestock and poultry because of extreme weather. Mahmuda Parvin hadn?t been able to grow vegetables for the past two seasons. After Cyclone Aila hit, Oxfam staff in Satkhira found Baburam rummaging for his belongings in the mud, having lost his home. Mahmuda Parvin?s home was swept away too. We found Mahmuda living on a highway, searching for food and water..."