China and India cover so many production environments that each can, to some extent, smooth out internal regional supply and demand variations via internal trade. Yet even these countries can benefit from this stabilising role of international trade. Wright (2012) shows that pooling the entire world’s output variation in rice production and sharing it proportionately across countries would reduce the variation of China’s and India’s shares by about 40% and 60%, respectively. For many smaller countries the effects would be far greater.