This paper defines three alternative approaches to technology development and adoption in international agriculture: Transfer of Technology, Industry-Led Technology Development, and Participatory Action Research. It assesses the strengths and weaknesses of each approach and examines the roles played by researchers, farmers, and extension workers. Although the Transfer of Technology approach has been quite successful in many developed countries and in selected developing countries, it is not always the most effective approach. In situations when private sector resources have been mobilized, the Industry-Led Technology Development approach can save public sector resources and can increase the relevance of the technology. When the broad involvement of numerous small-scale producers is necessary, the Participatory Action Research approach may be most effective. These approaches need not be competitors; flexible public sector institutions and personnel should participate in all three and be able to use them effectively in tandem.