Standard experiments on B. zonata and Ceratitis spp. were conducted during Phase 1 (2001), Phase 2 (2003) and Phase 4 (2005). In 2001, only C. rosa was present in the selected site. In 2003 and 2005, as populations of B. zonata and Ceratitis rosa were mixed in the experimental site, we could obtain results on the response of both species to the two series of tested attractants. Standard experiments on B. cucurbitae where conducted during Phase 1 (2001) and Phase 4 (2004). For all trials, experimental plots were chosen according to selection criteria which were the absence of insecticide treatments, the presence of a suitable fruit fly population, and the uniformity of habitat. All experiments were conducted following the standard protocols, except when otherwise mentioned. Data were analysed using ANOVA followed by Tukey's tests, alter logarithmic transformation (y = log (x + 1)). On the Natal fruit fly results in terms of most effective trapping system were not the same among years. In 2001 standard experiment, using 3C and comparing various retention systems or insecticides, showed that 3C + water + Triton was significantly more attractive than the other treatments for both sexes. In the 2003 standard experiment, significantly more females were caught with NuLure than with any other treatment. ln the 2005 standard experiment, the highest catches of females were obtained with Torula Yeast. On the peach fruit fly, B. zonata , in the 2003 standard experiment, the highest quantity of females was caught with the higher dose of Ammonium Acetate (2AA), which attracted significantly more females than the lower dose (1/2 AA) or any other treatment. As to the melon fly, B. cucurbitae, the 2001 standard experiment showed that Torula Yeast and AA were significantly more attractive than the other attractants for both sexes. However, AA appeared more selective than Torula Yeast, which caught significantly more non-target insects than all other treatments. In the 2004 standard e