How to define comparative agriculture? What can it offer to the analysis of agrarian realities and agricultural development processes? How did it become a driving force behind the proposals at the service of sustainable development? In the footsteps of René Dumont, Hubert Cochet offers a thorough analysis of comparative agriculture, based on twenty-five years of research and teaching carried out on site in France, as well as in many countries in Latin-America, Africa, Asia and Europe. In the first section dedicated to theoretical thoughts on comparative agriculture, Hubert Cochet introduces the notion of "agricultural development", the very subject of comparative agriculture, with a restored endogenous dimension. He then describes how this approach was slowly consolidated, around the concept of agrarian system in particular. The comparison of agricultural transformations in time and space highlights the importance of the comparatist approach to production processes, their trajectories and differentiation on a worldwide scale. The second section which focuses on the methods and expertise of comparative agriculture, tackles the issues of landscape analysis, field surveys and the historical approach underlying comparative agriculture. It sums up the economic tools mobilised as well as the evaluation perspectives opened up by comparative agriculture. This book which is at the crossroad of the social and life sciences, is meant for all those who wonder about the transformations of agriculture around the world, and who wish to change its course in the interest of the great majority. Agricultural Economist and Geographer Hubert Cochet is specialised in agrarian systems and their evolutions, as well as in the study of the impact of policies and development projects on their dynamics. As Professor of Comparative Agriculture at AgroParisTech (Comparative Agriculture and Agricultural Development Unit), he has conducted many scientific and expert's missions in various countries of the North and the South.