Technical Abstract: Tests were conducted to evaluate capture of Anastrepha obliqua, Anastrepha suspensa and other Anastrepha ludens in Multilure traps baited with synthetic food-based lures in areas with populations of these fruit flies. Traps were baited with putrescine and varying doses of ammonium acetate or ammonium bicarbonate. Captures in these traps were compared with capture in Multilure traps baited with two standard liquid protein baits – torula yeast/borax solution and Nulure/borax solution. Choice and no-choice, laboratory and field tests were used to compare among a variety of environmental and experimental conditions, and subsets of field-collected flies were dissected to determine sexual maturity of captured flies. Tests of A. obliqua were conducted in the Dominican Republic in mango orchards, tests of A. suspensa were conducted in various host fruit trees in Florida, and tests of A. ludens were conducted in citrus and sapote in Mexico. Results from parallel studies conducted for these and other Anastrepha species in Mexico, Central and South America as part of a CRB-funded research project and an IAEA-funded Cooperative Research Program will also be presented. This information will be used to develop improved trapping systems for Anastrepha spp fruit flies.