The largest famine in human history occurred in China in modern times and passed almost unrecognized by the outside world. Demographic evidence indicates that famine during 1958-61 caused almost 30 million premature deaths in China and reduced fertility very significantly. Data on food availability suggest that, in contrast to many other famines, a root cause of this one was a dramatic decline in grain output that continued for several years, involving in 1960-61 a drop in output of more than 25 percent. Causes of this drop are found in both natural disaster and government policy. The government's responses are reviewed and implications of this experience for Chinese and world development are considered.