The author specifies the factors which determine the choice of farming techniques in tropical countries : the national and regional environment, the state of science and techniques and the personality of the farmers. Even in a centralized economy, the farmers remain the decision makers in the farm sector and are the true innovators. This analysis predicts an increasing diversification of situations and farm models in the next twenty years. Consequently, there is no possible transfer in the purely agricultural field. The rural economist can only help the farmers to find their one way of development by using the existing production factors in the best possible manner. The technology transfers on the other hand are more easily operated in the food processing channels. Finally, the author believes that the new subjects of rural economic research in tropical countries will be the food supply to urban centers and the energy requirements of rural areas. The modernized farms will be the main actors of these new farm policies. Research structures have to be progressively adapted to these new constraints (divided according to products, disciplines and production systems).
