Deforestation, growing scarcity of tree products, and environmental degradation have created serious problems for rural land use in many developing countries. Agroforestry, a system in which woody perennials are grown on the same land as agricultural crops or livestock, has been increasingly enlisted in the campaign to meet these threats to the rural economy.Case studies of twenty-one agroforestry projects in six Central American and two Caribbean countries formed the empricial basis for the study described in this article. A focal point of analysis was the profitability of agroforestry for farmers as a crucial incentive to adoption.The findings indicate that many agroforestry practices are profitable under a broad range of conditions and are therefore likely to be widely applicable. Successful projects have worked with local communities, responding to local needs and preferences and offering farmers a broad basket of species and systems from which to choose. Demonstration plots and the use of paratechnicians have been low-cost and effective means of technology transfer, and applied research has been important in identifying techniques and practices suited to the region. Other findings have identified government regulation of tree harvesting and insecurity of tenure-though not lack of title in itself-as disincentives to adoption.