To evaluate the possible benefits of biotechnology for small-scale potato farmers, a field study based on interviewing these farmers in the mountainous areas of Mexico was undertaken during 1996-99. The objective was to inquire into several aspects of potato agriculture: origin of seed; inputs, costs and yields; production and seed commercialization; agricultural prices; farmers' general agronomic and socioeconomic situation (crop diseases, level of organization with other farmers and possible contacts with public or private institutions); and assessing the possible relevance of new biotechnologically produced varieties. The results of this case study are discussed. In addition, the paper provides information on potato production in Mexico, the CINVESTAV (Centro de Investigacion y Estudios Avanzados, Unidad Irapuato)/Monsanto programme on transgenic potatoes and assumptions from an economic model on transgenic virus resistant potatoes in Mexico.