In efforts to understand the process of agricultural develoµtent, economists and other social scientists have invested substantial resources in literally hundreds of studies of the adoption of new agricultural technologies. Recent reviews of these studies (Rogers, 1976; Byrnes, 1982; Feder, 1981) indicate that despite this large amount of research, there remain three major deficiencies in our empirical knowledge of the adoption of agricultural technologies. First, most adoption studies have had a "pro-innovation" bias that assumes that the innovation is "right" and that patterns of adoption therefore relate to the socioeconomic characteristics of the farmer. However, the extensive series of adoption studies completed by the CIMMYT Economics Program highlighted the fact that major differences in adoption of technologies usually arose from variation, sometimes subtle, in the agroclimatic environment (Perrin and Winkelmann, 1976). Farmers rejecting the technology were acting quite rationally because the technology was not suitable for their particular circumstances. The only farmer characteristic that consistently appeared as important in the CIMMYT studies was farm size and, even here, there was evidence that after an initial tine lag, small farmers usually adopted the same technologies as larger farmers.