The T-STAR Program, Tropical and Subtropical Agriculture Research, is funded by Special Research Grants (under Public Law 89-106) from the Cooperative States Research Education and Extension Service (CSREES), United States Department of Agriculture.   The program is designed to strengthen the research capabilities and economy of the United States' tropical-subtropical areas in the Caribbean and Pacific Basins.  Much of the research conducted in the temperate United States is not applicable to these areas due to the large differences in climate, soils, crops, insect and diseases, as well as socio-economic constraints.  Challenges include continuing plant disease pressure in the year-round growing season, control of alien pests and weeds in Caribbean and Pacific island agroecosystems and adjacent natural ecosystems, and post-harvest processing to extend shelf-life and preserve quality.  Opportunities include new germplasm collection, maintenance, breeding, and genetic engineering for novel products, value-added processing and marketing of tropical crops, and restoration and maintenance of healthy agroecosystems.  Regional agricultural research is critical to meeting the increasing challenges and opportunities in tropical island environments.