Technical Abstract: Multilure traps (Better World Manufacturing, Inc., Miami, FL) baited with BioLure MFF lures (Suterra LLC., Inc., Bend, OR) and containing antifreeze as the drowning agent, were about 2x more attractive than similar traps baited with AFF lures (Advanced Pheromone Technologies, Marylhurst, OR) in orchard tests with irradiated Mexican fruit flies (Anastrepha ludens) (Robacker and Czokajlo 2005). Although antifreeze originally was used in traps only to preserve the captured flies, Thomas et al. (2001) found that attraction of feral Mexican and Caribbean (A. suspensa) fruit flies to McPhail-type traps increased by twofold when antifreeze was used instead of water. Thomas et al. (2001) also reported that unbaited traps containing antifreeze captured flies, but no comparison with unbaited traps containing water was made. Hail et al. (2005) found that 10% propylene glycol was not more attractive than water, but the two drowning agents were not tested in the same trap type, so conclusive data about the attractiveness of antifreeze has not been published. The purpose of this work are: 1) to determine if antifreeze is attractive to Mexican fruit flies; 2) to investigate whether antifreeze enhances attractiveness to the AFF lure; and 3) to compare performance of AFF lures and BioLure MFF lures in traps containing antifreeze vs. water.