Despite their success in boosting cereals production overall, the Green Revolution programs of the 1950s and 1960s were often criticized for failing to achieve their declared aim of alleviating world hunger. Most critics argued that the programs had produced a technology unsuited to the needs of small peasant farmers. This paper explores why such inappropriate technology might have been developed, focusing on the early years of the Rockefeller Foundation’s Mexican Agricultural Program (MAP). It shows that some foundation officers as well as agricultural advisors had prior experience of the problems faced by small farmers in the United States and elsewhere.Moreover, the foundation’s expressed concern for rural poverty does not appear to have been mere posturing by an organization anxious to be seen as an agent of philanthropy. Furthermore, the program’s early work in maize-breeding was well tailored to the conditions of Mexican agriculture.Once the MAP was up and running, however, it became apparent that the task of getting new varieties and cultivation practices to small farmers was going to be difficult. Needing to make some kind of impact quickly, MAP staff chose to concentrate upon projects that were likely to find a rapid uptake. This meant setting aside the needs of peasant farmers to develop high-yielding varieties suited to large commercial farms.