Examines the application of biotech. to agricultural development, assessing farmer-based as well as science-based biotech., & the socio-political context. Looks at rural people's existing biotech. practices in the areas of animal health, bio pesticides, food processing & crop genetic resources. Assesses science-based biotech. research, the potential of existing technologies & the socio-political context of formal sector research. Presents a methodology for the development of biotech. for small-scale farmers in the tropics, & integrating farmers' knowledge. Sets out a model for integrating the formal & informal R&D systems.