This study attempts to draw the first lessons of the World Bank experience in building the capacity of rural producer organisations (RPOs). From 1997, the World Bank and French co-operation provided support for the preparation and implementation, in developing countries, of new projects to support agricultural services and rural producer organisations aimed at promoting services driven by producers' demands. They also constituted institutional innovations for the following three main reasons: - They are aimed at building institutionalised partnership between rural producer organisations and research and extension bodies. Such partnership should enable organised producers to (i) express collective demand for support to technical and economic innovation and (ii) influence the orientation of, and decision-making within, the service bodies concerned. - The World Bank provides its support to (public and semi-public) institutions responsible for agricultural services and to rural producer organisations in order to build their capacity and to create conditions for equitable dialogue between the different partners. - These projects are accompanied by institutional reforms, which each country implements at its pace but which are aimed at rendering research and extension institutions accountable to producers. The first projects were carried out in Senegal, Guinea, Mali and Burkina Faso. Thereafter, the approach was gradually extended to other sub-Saharan African countries and to North Africa (Tunisia, Morocco), and demand for similar projects is growing in Asia (Indonesia, India). [...] This report is structured as follows: - Part one presents a brief analysis of the relationship between research and extension institutions and producers' organisations and the developments in this relationship over a long period of time. It lays emphasis on (i) factors that explain the growing importance of the role of RPOs in the innovation process and (ii) the activities sponsored by the var