Debates over the last few years concerning the future of the planet have seen the question of food sufficiency reappear. With the world's population growing at an ever-increasing rate and an extra 1.7 million mouths to feed each week, the Malthusian fears of a widening gap between people's needs and food production are once more coming to the fore (Brown, 1995). The threat of medium or long term hardship is directing public attention to the need for a new international effort to increase food availability. However, half a century of agronomic research has shown that that the problem cannot be defined simply in terms of chasing after a constantly rising demographic curve and proposing more productive crop varieties. New priorities have emerged which are not solely production-oriented, but show that one of the crucial questions for the future of the planet is the relationship between production and consumption, in other words the food sector (processing, storage, transportation, marketing and trading activities). How can food sector contribute to meet new challenges triggered off by demographic growth and urbanization, globalization of trade, environmental damages, and widening disparities? What can be learnt from research and development carried out in tropical countries over the past decades? Which are possible new directions for research and development to face new challenges? The objective of this paper is to try to bring elements to answer such questions. Most of the content of this paper has been extracted from a more detailed synthesis which was recently published in Outlook On Agriculture (Raoult-Wack and Bricas, 1998).