Since 2007, unusually large numbers of rats have been flooding out of the forests of the Chittagong Hill Tracts (CHT), causing major suffering and hardship for local communities. These rat floods in the CHT are a real and scientifically accepted phenomenon, and similar events are known to periodically occur in many parts of the world. Because there are suddenly so many rats, communities don't know how to control the problem, and the rats are devouring everything they can find in farmers' fields and houses. [...] In this past year, the World Food Programme has been delivering emergency aid to some of the affected communities, but more needs to be done to deal with growing food shortages and other potential implications. Because it doesn't happen often, little is scientifically understood about rat floods. This lack of knowledge has been recognised, particularly by the United Nations Development Programme which recently commissioned a team of scientists to gather together all the existing knowledge.