Résumé
This paper presents the evolution of a research program on farming systems carried out by EMBRAPA-CPATSA, in concurrence with CIRAD-SAR, in northeast Brazil. The program had the initial objetictive of going beyond the experimental station towards the true situation in the rural farm. naturally fitting to the problems of the agricultural process and evolving to a stage of studs of development processes at regional level. For each of the stages identified, questions, main objectives, concepts, methods, available resources. institutional policy, observed results and limitations are presented and discussed. From this analysis, the main consequences and/or perspectives of the program actions are characterized i the final considerations, concerning the knowlege formation, evolution of concepts and methods, institutional improvement and participation in the process of regional development. (Résumé d'auteur)